senator bernie sanders is moments away from getting a walk-through of tonight's cnn debate stage weeks after suffer aing heart attack and as the vermont senator and 11 other democratic presidential candidates prepare to take to that stage in a few hours, so much has happened. since the last debate, 33 days ago from the impeachment inquiry to the white house shifting gears in syria. also witnessed senator elizabeth warren's rise in polls and former vice president joe biden rigorous defense of his son hunter. go to may reston live at the debate side in westerville, ohio, and, maeve, start with senator sanders. wish hem well healthwise, standing on the stage fresh off his heart attack what message does he need to relay saying i'm ready and fit to serve? >> reporter: has to show he is really back in the game. obviously this heart attack wag a lot more serious than everyone