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The numbers are in - an estimated 24 million Americans watched the first Republican presidential debate last night on Fox News, and the candidates did not disappoint. It was lively from the first question. Today, the candidates who did well are trying to press their advantage while others are trying to move on. We begin with NPR's Scott Horsley.
SCOTT HORSLEY, BYLINE: The television audience for last night's debate was three times as large as the most-watched primary contest four years ago. And there was enough additional traffic online to overwhelm the Fox News servers. Political analyst Jack Pitney of Claremont McKenna College says there just one explanation for that record tune-in - Donald Trump.
JACK PITNEY: In an odd way, he actually helped the other candidates. Millions of people tuned in just to watch the Donald Trump show. But in the process, they saw the other candidates as well, and some of them may have come out of that with a good impression of some of those other candidates.
HORSLEY: Whether Trump helped himself is another story. Informal surveys suggest Trump's core supporters were again impressed by his frank-talking stage presence. But other Republicans may have been turned off when Trump said he'd only promised to support the eventual GOP nominee if it's him.
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DONALD TRUMP: I can totally make that pledge. If I'm the nominee, I will pledge I will not run as an independent. But I'm, you know, talking about a lot of leverage. We want to win, and we will win.
HORSLEY: A Fox News focus group showed voters turning away from Trump during the debate. Asked about that this morning on NBC, Trump was characteristically unchastened.
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TRUMP: That was done by a guy named Frank Luntz, who is a real dunce, frankly. I don't know where he finds the people, but I think he picks them - I think he handpicks them to say whatever they want because it didn't jive with anything.
HORSLEY: Other top candidates, like Jeb Bush and Scott Walker, mostly treaded water during the debate, while Marco Rubio made a splash as the smiling face of the GOP future.
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MARCO RUBIO: First, let me say I think God has blessed us. He's blessed the Republican Party with some very good candidates. The Democrats can't even find one.
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HORSLEY: And one of the biggest winners of the night was apparently Carly Fiorina. The former CEO of Hewlett-Packard barely registered in polls taken before the debate, and she failed to qualify for the prime-time telecast. Fiorina impressed many observers, though, with a strong showing in an earlier forum for second-tier candidates.
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CARLY FIORINA: I think to be commander in chief in the 21st century requires someone who understands how the economy works, someone who understands how the world works and who's in it. I know more world leaders on the stage today than anyone running, with the possible exception of Hillary Clinton.
HORSLEY: The audience for that early forum was only about a quarter the size of the prime-time debates. But Pitney says the resulting buzz could still give a boost to Fiorina's struggling campaign.
PITNEY: This morning, Rush Limbaugh was praising her. And that's very important because people listen to Rush Limbaugh, and some of them are in a position to write checks to candidates. And I suspect Carly Fiorina's fundraising is going to pick up as a result.
HORSLEY: Pitney cautions against drawing too many conclusions from this midsummer face-off with many months to go before the first primary votes are cast next winter. We're still in what he calls the entertainment phase of the presidential contest when most people aren't thinking seriously about who they want to see in the White House. There is an exception, though. Democratic opposition researchers paid close attention to last night's debate. They'll be carefully cataloging every word the candidates uttered, looking for ammunition they can use in next year's general election campaign. Scott Horsley, NPR News, Washington. Transcript provided by NPR, Copyright NPR.