it may well be we're working with a couple of segregations that got bills passed but a lot of young people today don't think you ought to celebrate that. you shouldn't celebrate segregationist. you should oppose them and i think he missed that, he missed that in his comments. >> david, i want to ask you about the university poll that shows joe biden out in the lead but shows elizabeth warren we've seen again and again in the polls vaulting up into this clear second tier either tied with or slightly ahead of bernie sanders. what's behind this war and momentum and who should be concerned about it? which other candidates should be concerned about snit. >> bernie sanders should be concerned. you're right. that's a tie there. 15% to 14% between the two of them. they are fighting over a swath of territory that involves a lot of the same voters, right? we saw in our iowa poll, john, that among sanders' supporters in the iowa poll, elizabeth warren was the second choice for a third of them.