Could some of your Favorite Foods increase your risk of lung cancer even if you dont smoke in. One heck of a save. One dad hailed as a hero for stopping a flying baseball bat from hitting his son. Nightly news begins right now. Announcer from nbc news World Headquarters in new york, this is nbc nightly news with lester holt. Good evening. A new nbc news wall street journal poll just out tonight is showing how tight the race is for president. Donald trump leading by just three points nationally. Trump is at 30 , cruz in second at 27 , but inside the margin of rubio trailing behind. The poll comes as republicans are voting today in four states. But it is next weeks primaries in delegaterich ohio and florida that many expect could blow the gop race wide open. Democrats, meantime, are in michigan, a state key to Bernie Sanders survival. Tonight our poll Shows Hillary clinton leading sanders nationally by nine points. We have it all covered starting with nbcs katy tur. Reporter gop voters casting ballots in four states for four remaining candidates. But right now it is looking more like a twoman contest. Tonight an nbc news wall street journal poll finding donald trump and ted cruz locked in a tight race nationally with six states under his belt, the texas swagger. So of course, donald is upset, and i will predict he will engage in more attacks, they will be more personal, they will be more nasty. Reporter tonight battles in indicators. Both open primary states where independents or democrats can cast republican ballots. If donald trump has trouble in michigan or mississippi tonight, well see that the establishments attempts to try reporter now the former no many knee, mitt romney, now leading an establishment move to stop the outsider. Today this attack ad. Romney also voising antitrump robo calls for john kasich and marco rubio in states voting today. Im convinced donald trump will lose to Hillary Clinton. Reporter the new yorker trading the trail for tv defending his voter pledge on the today show which critics say invokes nazi germany. I get by far the biggest crowds. Until this phone call i didnt know it was a phone call. Reporter a former head of the antididnt Defamation League disagree. Tonight trump hoping to keep his momentum in the face of what could be a changing race. Needs to win early. If these results come in late it means it is a much closer race than anticipated and that the attacks against him could be working. Katy, now to the unfolding democrat story. All eyes on the michigan race where Bernie Sanders finds himself at a crucial juncture. As nbcs kasie hunt reports, it could be a makeorbreak night for his campaign. Reporter for Bernie Sanders tonight, voting in michigan is a critical showdown. Michigan has the opportunity to move this country forward toward a political revolution. Lets do it thank you reporter todays primary likely his last chance to prove hes a real contender. This has been a very significant state for me and for secretary clinton. Reporter sanders is winning smaller states, but so far hes fallen behind in the big diverse states where more delegates are at stake. Hes running out of time as we get into march 15th and going to have to have an unexpected win in order to change the trajectory of the race. Reporter in michigan sanders is closing the gapt, drawing huge crowds on College Campuses and union halls from the working class hit hard by the collapse of the auto industry. People are scared. They want to know that their future. Reporter as polls open, sanders was on defense after Hillary Clinton accused him of voting against the auto bailout. Michigan voters deserve tactics. Please go out and vote today. Reporter Hillary Clinton looking ahead in ohio tonight. Her husband already in illinois. And eager to start running in the general election. The sooner i could become your nominee, the more i could begin to turn our attention to the republicans. Reporter sanders today dismissing questions about whether he should step aside. Do you have any real questions . Reporter promising his supporters hell press on. Voters are also going to the state where clinton is expected to do well. If thats the case she could actually add to her pledged delegate lead even if she struggles in michigan. Let me turn now to chuck todd, nbc news political director and moderator of meet the press. Chuck, what should we watch tonight . Want to see was saturday and indication of something happening in the antitrump movement . Are antitrump forces coalescing . Is it around ted cruz . Is it around john kasich . Interesting the big winner out of our nbc news wall street pornl was poll was john kasich. But i think the big story tonight is whether trump can win by double digits in both states as he should, or have is the antitrump forces closed the gap and does he struggle in both. On the democratic side, it is all about what kasie just reported. Can Bernie Sanders win . His issues, if he cant win in michigan, where is he going to win against Hillary Clinton in a big state . Big test for Bernie Sanders tonight. I think it is make or break. Tens of millions are on alert in the south tonight for more extreme weather. At least one person has already been killed by a mass of storm system in texas. The violent weather leaving a path of destruction in its wake and the Severe Weather threat is expected to last for days. Nbcs janet schamlian has the details. Look at all that stuff flying around. Oh thats a tornado. Reporter the south under siege. 26 million in the path of todays Severe Weather. At least one tornado near ft. Worth in hood county, texas. I looked outside and i seen the roof coming off. Then it was swirling around. Before i had to chance to go get under cover, it was gone. Reporter jimmy watched helplessly from his living room. A dozen mobile homes in his neighborhood were torn apart. He pulled people out from piles of debris. I didnt think i was going to find anybody in there alive. Storm started in texas but are moving north carrying moisture from the gulf set offing up potentially dangerous flooding. Tornado and flash flood watches in six states, all the way to illinois. In denton, texas, children trapped on a school bus. Rescuers wading through the rising wraert rise ing water to pull six of them and their driver to safety. In grain pevine, an 18wheeler flipped by high winds turned and interstate into a parking lot. Gusts topping 70 miles an hour pulled bricks from the state of the union at Tarrant County college. Severe weather conditions continue through at least tomorrow and will deliver in some areas a foot of rain. Investigators believe a mudslide and a downed tree on the tracks may have caused a passenger trail to derail in Southern California causing the lead car to plunge into a creek below. Injured, four seriously. The accident happened after hours of heavy rainfall. Dramatic new video is out tonight showing one of the leaders of that armed oregon occupation in his final moments. State Officials Say their investigation shows police were justified in using deadly force against him. But as our Pete Williams reports, the video raises a new mystery over who fired shots at him, and when. Reporter cell phone video captures the moment the first shots were fired. Hang on reporter oregon investigators released it today, recorded inside the suv driven by the leader of the 41day occupation of an oregon wildlife refuge. Taking from the cell phone of one of those charged in the occupation, it shows him driving barreling toward a police road those three shots. After crashing into a snowbank, says go ahead and shoot me. Go ahead and shoot me. Go ahead and shoot me. Stay down. Stay down. Stay down. Stay down. Reporter Oregon Police say officers on the scene had been told that he routinely carried a gun. Police say he twice ignored commands to get on the ground and twice reached for what they thought was his gun. The third time, two Oregon State Police officers fired three shots in all. Are they shootsing him . Did they shoot him . Reporter striking him in the back and killing him. A gun was found in his left jacket pocket. He was reaching for that loaded 9 millimeter gun when the troopers lawfully used Deadly Physical force. Reporter still unanswered tonight investigators say one, possibly two other shots were fired that did not hit anyone. State investigators say fbi failed to disclose that they fired them, but the fbi says the agents did not fire. Thats now under investigation, too. Pete williams, nbc news, washington. Killed today in a stabbing rampage in israel, Vanderbilt University says his name is taylor forest, a graduate student who was on a school trip. At least ten others were injured in the stabbings in tel aviv before the attacker was shot dead. Joe biden condemned the attack on social media calling it an act of terror. Two of the jurors who handed erin andrews a 55 million verdict are now spishging out ing speaking out. The Sports Reporter won her suit yesterday against the stalker and the hotel who secretly taped her. As she jurors tell our morgan radford, it was not a question of if andrews would win, but how much she would get. Reporter breaking her silence. She was honest as far as i knew. She was emotional. Reporter for jurors like these, it was hearing from erin andrews that made the difference. Erin andrews is going to get it was how much and where was the hotel at fault. Reporter what affected you the jury box . A woman who has built her career in a mandominated industry and has done well. And i think outside of this incident, her life, her character, should be a role model for every young girl growing up. And she said the same. Girls, high school, college, they treat me. They say i want to be erin andrews except for the marriott stalker think. I cant control that. Reporter the average civil award in tennessee last year was just over 400,000. Andrews won more this week than all of the tennessee awards last year combined. But she may not see much of it since her stalker, michael barrett, was clear that he made was broke and the juror says this case wasnt about celebrity. It was about safety. It is important when we walk in a hotel or any public building that says theyre going take care of us. Now to the urgent warnings over the zika virus in puerto rico. Health officials predict 1 in 5 there could become infected. The fda is shipping down blood over fears that local supplies could be contaminated. Tonight the head of the cdc is there calling puerto rico ground zero for the fight against zika in the u. S. Nbcs rehema ellis has more from san juan. Reporter in this hospital Maternity Center in puerto rico, there is growing fear of zika, expected to infect hundreds of thousands on the island. No you we have to test everybody and repeat those tests as pregnancy advances. Reporter researchers learned zika can inspect an unborn baby just the first trimester as previously suspected. Reporter it the cdc director ramping up the battle to stop zikas spread to the u. S. Mainland. This is the front line. Absolutely. There are going to be more cases in puerto rico than in the rest of the u. S. By many, many, many multiples. So this is going to be ground zero for zika outbreak in the u. S. Can you stop it . We dont know how to stop deska. Reporter zika. Reporter puerto rico hit especially lard because it has the kind mosquito carrying the virus now become ing ing unaffected by certain incestcides. This woman, 18 weeks pregnant with her second child, cried when she learned she had zika. I got really scared. Reporter her unborn baby far. Shes using mosquito spray and hoping for the best. My break is a blessing and im going to have it. So no matter what happens, im going to have this baby. Reporter the risk to control the virus intensifies. Still ahead, the question that gave us pause when we heard it. Is there a link between carbohydrates and lung cancer . Surprising new research raising questions about the foods so many of us love to eat. Also a day at the ballpark that almost ended in disaster. If it werent for a dads quick some Important Health news tonight about something in the foods a lot of us eat that could be a contributing factor for lung cancer. While the vast majority of lung cancer cases are linked to smoking, researchers say new evidence suggests diets heavy in certain carbs may also play a role for nonsmokers. Nbcs tom costello explains. Reporter its the leading cause of cancer deaths in the u. S. , more than 150,000 people expected to die from lung cancer this year alone. The vast majority current or former smokers, but 15 are nonsmokers. Now, Surprising Research has found a potential lung cancer risk factor for them. Certain foods that quickly elevate a persons blood sugar level, socalled high glycemic foods. They tend to be processed, tend to be white, kind of starchy carbohydrates with a lot they dont tend to have a lot of fiber or other nutrients in them. Reporter the m. D. Anderson Cancer Center studied 1,900 lung cancer patients. The biggest surprise, patients who had never smoked were more than two times as likely to develop lung cancer, yet if they had eaten foods high in starch and sugar, mostly processed food including foods like white bread, bagels, popcorn and processed food like corn flakes, saltines and pretzels. Researchers believe the sudden blood sugar spike can affect the way cells grow, something they have also seen in other cancers. What this does is it causes insulin resistance in the cells, and these lead to potentially increasing growth factors that are associated with the development of cancer. Reporter doctors say its far too early to conclude white bread leads to cancer, but a lean diet with plenty of fruits, veggies and lows glycemic carbs is always a healthier choice. Tom costello, nbc news, washington. Were back in a moment with a close call that totally shocked sponsors are distancing themselves from Maria Sharapova after the tennis superstar admitted testing positive for a banned substance. Nike, porsche and luxury watchmaker tag heuer suspended ties. Sharapova claims she didnt know meldonium, a medication she used for a decade, was added to the banned list at the start of the year because she didnt open an email link from doping officials. A tv reporter from Northern California almost became news himself when this happened live on the air. A confusing situation for a car came barreling right at alex savage and his camera operator, both barely managed to get out of the way. The vehicle had just been involved in an accident sending it careening off the road. Amazingly no one was injured, but what a close call. And talk about a close call. Captured the moment a small plane nearly landed smack on a building on long island, new york. The faa says the plane lost engine power and had to pull off an Emergency Landing with the planes builtin parachute. Moments later the father and daughter inside the plane can be daughter inside the plane can be seen walking away safe and sound. And one more near miss. When we come back a baseball bat comes flying at a young fan, but, boy, did his dad act finally tonight, the nearmiss thats making jaws drop across the country. A spring training baseball game where the fastest reflexes werent on the field but rather in the stands when a dad saved his son from almost certain injury. Nbcs joe fryer has the story. Reporter for Landon Cunningham who is turning 9 next week, it was the ultimate early Birthday Gift, the trip to the ballpark to catch a spring training matchup where the play of the game would be made by his own dad. He is a hero. Reporter 30, rodrigues runs. The bat goes into the seats. Whoa, whoa, whoa, whoa, whoa. Reporter you could hear the crowds reaction on the Pirates Radio Network as a bat slipped from the hitters hands hurtling towards the third row where landon was looking down at a phone about to send pictures to his mom. Scared. Reporter the images captured frame by frame by the Pittsburgh Tribune review. Look at the expressions of those around landon and then look at calm reaction of his father sean whose instincts set in like a catcher blocking a wild pitch. I didnt have a lot of time to think about it. It just the only thing i can describe it as is dad mode. Reporter granted, this dad played college ball and was even drafted by the pros before getting sidelined by a shoulder injury. Now a firefighter, his baseball skills came in handy one more time, saving his son. I just kind of whispered to him, like landon, hold your head up and tip your cap. He held his hat up and did that and the whole stands cheered and applauded. It was really cool. Hes like dad, that was awesome. Reporter as for landon. I asked my dad is this what usually happens at baseball games . Reporter he got to keep that bat as a souvenir. Consider it the Birthday Gift he never saw coming. Joe fryer, nbc news. Nice save, dad. That will do it for us on a tuesday night. Im lester holt. For all of us at nbc news, thank you for watching and good night. A new day, same kind of storm, snow in the high country and rain snow mix in the denver area. Were expecting showers in the city in the next few hours and bring it o a new report has the state wide snowpack levels revel in the warm weather but the consequences are upon us. We can catch up in a hurry, kyle, and you know we are in the snowiest months, and one snow event can bring us up above average in march. And we are watching moisture off to the south and west and well have to see if that make its over the urban corridor in the form of a brief snow or rain. And all the Winter Weather travel advisories are south of our area, and we are tracking an area of low pressure from the west. And hail, tornadoes, and flooding rain down to the south, and a couple of sprinkles tonight, not going to last very long. The skies will clear and it will be pretty darn cold tonight. We are partly to mostly cloudy and roads are dry and temperatures in the mid40s. Coming up in the main weather segment, well talk about a mid