Hillary Clinton trounced Donald Trump in Monday night’s debate — the first of three slugfests between the two candidates, according to a poll of voters who viewed the showdown.

Sixty-two percent of voters who tuned into the debate at Hofstra University backed the Democratic nominee, while only 27 percent said they thought The Donald pulled it off, according to a CNN/ORC Poll.

By a margin of more than 2-to-1, voters said Clinton expressed her views more clearly and had a better understanding of the issues.

She also was seen as having better addressed concerns about her potential presidency by a margin of 57 percent to 35 percent — and as being the stronger leader by 56 percent to 39 percent.

The gap narrowed on which candidate appeared more sincere and authentic, but Clinton still came out on top, with 53 percent saying she was more sincere vs. 40 percent who felt Trump did better on that score.

Trump was viewed as the debater who spent more time attacking the opponent by 56 percent to 33 percent.

Debate watchers were more likely to describe themselves as Democrats than the overall pool of voters, the survey suggested, but independents who watched deemed Clinton the winner, 54 percent to 33 percent.

Clinton also outperformed the expectations of viewers. Pre-debate interviews indicated these watchers expected Clinton to win by a 26-point margin, but that grew to 35 points in the post-debate survey.

About half in the poll said the debate did not affect their voting plans — 47 percent said it didn’t make a difference — but those who say they were moved by it shifted in Clinton’s direction. Thirty-four percent said the debate made them more likely to vote for Clinton, 18 percent more likely to back Trump.

On the issues, voters said Clinton would do a better job handling foreign policy, 62 percent to 35 percent, and most think she would be the better candidate to handle terrorism, 54 percent to 43 percent.

On the economy, 51 percent said they favor Clinton’s approach vs. 47 percent who prefer Trump.

Most watchers expressed doubts about Trump’s ability to handle the presidency.

Overall, 55 percent said they didn’t think Trump would be able to handle the job of president while 43 percent said they thought he would. Among political independents who watched, it’s a near-even split, with 50 percent saying he can handle it and 49 percent that he can’t.

The CNN/ORC post-debate poll includes interviews with 521 registered voters who watched the debate. Results among debate-watchers have a margin of sampling error of plus or minus 4.5 percentage points.