HuffPollster reports the results of "scientific" polls via email.
HUFFPOST/YOUGOV POLL SHOWS A WIN FOR CLINTON - HuffPollster: “Hillary Clinton scored a decisive debate victory over Donald Trump, coming off as more presidential and better prepared, according to a new HuffPost/YouGov poll. By a 27-point margin, 49 percent to 22 percent, Americans who had heard at least something about Monday’s presidential debate said that Clinton did a better job than Trump. Twenty-two percent said neither had done a better job, while 8 percent were unsure. Those results are broadly in line with other scientific post-debate polls, which also found a sizable advantage for Clinton….Seventy-seven percent of those polled, including a majority in both parties, said that Clinton prepared well enough for the debate, compared to just 27 percent who said the same for Trump. Even 43 percent of Republicans said that Trump should have done more preparation….Those who watched at least part of the debate said by a 30-point margin, 53 percent to 23 percent, that Clinton won, while those who watched highlights or read news stories said so by a narrower 17-point margin, 35 percent to 18 percent.” [HuffPost]
As does NBC/SurveyMonkey - Hannah Hartig, John Lapinski and Stephanie Psyllos: “A majority of likely voters (52 percent) who either watched the debate or said they followed debate coverage in the news said Hillary Clinton won the first presidential debate on Monday night, according to the NBC News|SurveyMonkey Debate Reaction Poll. Just 21 percent of likely voters thought Donald Trump won the debate, and 26 percent said neither candidate won the debate...Though voters agreed Clinton was the clear victor, a majority of voters overall said their opinions of either candidate did not change as a result of the debate. Clinton, however, seemed to boost her image among her own party as a result of her performance — 50 percent of Democrats and Democratic-leaners said their opinion of her changed for the better as a result of Monday night’s debate. Trump did not have quite the same effect on his own party.” [NBC]
So why does Trump claim victory? He was relying on non-scientific reader polls. HuffPollster, explains the difference: -A quick refresher on the difference between scientific polls and reader polls.