It was a fierce showdown in which major issues were discussed sporadically or not at all, and personal exchanges erupted every few minutes. But the first presidential debate between Hillary Clinton and Donald Trump allowed voters to assess the candidates side by side, under pressure, with everything at stake. And on most gauges, Clinton won.

She was unflappable, confident but not cocky and deeply knowledgeable about policy, if a bit too cerebral and wonkish. Trump was strong but overbearing at times and light on policy details, and showed difficulty restraining himself, often interrupting Clinton with sharp attacks or blustery outbursts.

And the worst may be yet to come for Trump. That’s because many voters don’t immediately come to conclusions about the winner and loser of a presidential debate. This assessment is frequently shaped by media coverage and the debate-based political commercials that emerge in the days that follow. And Trump is likely to fare badly in those stories and in ads by Clinton and her allies because he made himself such a target for criticism.

His manner was a particular problem for him. Trump seemed to get agitated as he grimaced, smirked and rolled his eyes while Clinton was speaking. In contrast, the well-rehearsed Clinton smiled calmly and seemed bemused while was Trump was talking. All this was captured on a split screen throughout the debate, and will be a ready-made source for attack ads and media commentary.

Initial fact-checking by news organizations found that Trump, the Republican nominee, made more misstatements than Clinton, the Democratic candidate. The Washington Post found that Clinton stretched the truth on occasion but her errors “paled in comparison to the list of Trump exaggerations and falsehoods.” The New York Times arrived at a similar conclusion, noting, “In keeping with how he has run his campaign, Mr. Trump stretched the facts more often than Mrs. Clinton did; a couple of times, Mrs. Clinton literally called out for fact-checkers from the stage.”

Among the falsehoods: Trump’s claim that he had opposed the 2003 U.S. invasion of Iraq beforehand, which has been labeled false many times by media fact-checkers. He also had trouble dealing with the “birther” issue, failing to explain why he had recently acknowledged that Barack Obama, the first African-American president, was born in the United States after questioning his citizenship for years, long after Obama’s citizenship had been established. Clinton condemned Trump for perpetuating a “racist lie.” All this will probably hurt Trump’s efforts to appeal to African-American voters, and is likely to turn up in anti-Trump commercials and media analysis.

Trump’s best moments came when he portrayed himself as the candidate of change and blasted Clinton, former secretary of state, former U.S. senator from New York, and first lady for eight years while her husband was president, as a failure who was unable to solve major problems. He conceded that she had experience but said “it’s bad experience.”

Yet Trump was easily diverted from these larger themes and spent much of the debate on lesser issues. Clinton successfully goaded Trump throughout, and he jumped at the chance to respond to her needling.

Trump also walked into traps he inadvertently set for himself. At one point, he repeated his frequent charge that Clinton lacks the stamina to be president. But she replied that her record proves this false. “If he travels to 112 countries and negotiates a peace deal, a ceasefire, a release of dissidents, an opening of new opportunities in nations around the world, or even spends 11 hours testifying in front of a congressional committee, he can talk to me about stamina,” she said.

Further contradicting Trump’s point, Clinton showed no evidence of fatigue or lack of energy during the 95-minute debate while Trump sometimes seemed miffed or short-tempered and gulped frequently from a glass of water as if he needed to refresh himself or preserve his voice. There were no signs of the pneumonia that nearly caused Clinton to collapse at a public event two weeks ago.

Clinton, who would be the first woman president of the United States if she wins, also pivoted effectively by turning Trump’s questioning of her stamina into a reminder that he has spoken harshly of women. “This is a man who has called women pigs, slobs and dogs,” she said.

Trump has been gaining on Clinton in national polls–the latest surveys indicate a statistical tie–and he has edged past her or tied her in battleground states such as Colorado, Ohio and Pennsylvania.

It’s not clear whether the debate will stop or slow Trump’s surge because so many of his supporters, especially working-class men, are still deeply committed to him. Many voters like his message of change and his pledge to fight the political establishment even if he is a flawed candidate. But it’s hard to see how he helped himself in courting key constituencies such as minorities, women and college-educated voters.

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Clinton may have bolstered her support among women and minorities but may not have been effective in courting young people and other constituencies she badly needs to win over.

The debate was held at Hofstra University in Hempstead, New York.

The next presidential debate is scheduled for Oct. 9 in St. Louis, and the final debate is Oct. 19 in Las Vegas. A vice presidential debate is scheduled for Oct. 4 in Farmville, Virginia.

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Clinton Comes Out on Top in First Presidential Debate originally appeared on usnews.com