The instant post-debate analysis Monday night on cable and broadcast news networks credited GOP presidential nominee Donald Trump with a strong start on issues such as trade and jobs, but said Clinton was more consistent during the rest of the debate.

“I thought those first 20 minutes, half-hour of the debate, he was really doing well,” said CNN’s Jake Tapper. “The other hour-plus of the debate, not so much.”

Fox News’ Brit Hume said Trump was effective in the first 10 to 15 minutes, but ran into trouble on the “birther issue” after moderator Lester Holt asked why it took five years after President Obama released his Hawaii birth certificate for Trump to agree that Obama was born in the United States.

Fox’s Dana Perino said Trump had strong points, hammering Clinton on the Trans-Pacific Partnership trade deal, which Clinton previously supported but now opposes.

But Perino said that later, “Donald Trump was on his heels” on issues such as the Iraq War, which he insisted he always opposed despite being pressed by Holt that he did not. Trump shouldn’t have spent so long defending himself on the issue, Perino said.

Even former New York City Mayor Rudy Giuliani, a frequent surrogate for Trump, tweeted that Trump “did great at the beginning of the debate, then was ok. But we still have more debates to go.”

Yet Trump himself said in a post-debate interview of his own performance that “I think it went better than I ever thought.”

NBC’s Tom Brokaw said, “Hillary’s composure and mastery of detail was consistent throughout” and she had a pleasant demeanor.

Trump, he said, “probably kept his constituency,” but likely did not pull in new voters — echoing what several other commentators said.

NBC political contributor Nicolle Wallace said Clinton “certainly looked more presidential,” although she said that this year, it’s unclear how helpful that would be.

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Tucker Carlson, of the conservative Daily Caller, said that by one measurement, Trump did well.

“I think Trump won because he didn’t melt down,” he told Fox. “I mean, it was a low threshold.”

CNN brought together 20 undecided voters in Orlando, in the key battleground state of Florida, to watch the debate. Afterward, 18 believed Clinton won the debate.

Those who judged Clinton the winner used terms like “well-prepared” and “even-keeled.” One of the two voters who said Trump won said Clinton failed to assuage concerns he has about her.

A CNN/ORC poll of 521 registered voters directly after the debate found that 62 percent thought Clinton won the debate, while 27 percent believed Trump won — although the network cautioned that the viewers skewed more Democratic than the electorate as a whole. The poll did not account for the other 11 percent polled.

CNN’s Byron Pitts said Trump’s attempt to appeal to African-Americans during a debate segment on race relations likely fell flat, while “I think Hillary did what she needed to do with black voters.”

Van Jones, a generally liberal commentator on CNN, said Trump’s continued defense of the NYPD’s stop-and-frisk policy — which was eventually ruled unconstitutional — and his advocacy to initiate such a policy in Chicago and other cities, hurt him among black voters.

“They stopped thousands and thousands of innocent African-Americans” and worsened relations between police and the black community, Jones said.

CNN’s Gloria Borger said Trump’s remark that he was “smart” not to pay federal taxes in the past hurt him among voters who do pay taxes, although after the debate, Trump said to CNN’s Jim Acosta, “Of course I pay federal taxes.”

Talk-radio host Michael Smerconish said on CNN that Trump didn’t do a good job of keeping his cool.

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“He was trying to explain he had the temperament [to be president], but his volatility kept rising,” he said.

Megyn Kelly of Fox put Trump’s performance in perspective when she reminded viewers that in 2012, Republican nominee Mitt Romney was widely seen in the first debate as the overwhelming winner against Obama, who recovered in the next debate and won the election.

NBC’s Chuck Todd said it wasn’t Trump who was “the big loser,” but the American public, because of a “lack of substance” on the part of both candidates, who spent most of their time attacking each other and touting their own candidacies.

“They spent 75 minutes talking about themselves,” Todd said.