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Donald Trump will be in the spotlight - or maybe the line of fire - when Republican presidential candidates hold their first televised debate this week. Jeb Bush and Scott Walker will also share the primetime stage. But former Congressman Rick Santorum might not make the cut, despite winning the Iowa caucuses four years ago. Fox News is relying on national polls to decide which candidates are included in the marquis debate and which are relegated to an earlier warm-up program. NPR's Scott Horsley reports.
SCOTT HORSLEY, BYLINE: Thursday's debate will be as crowded as any in U.S. history, with 10 candidates sharing the stage. Democrats had just eight back in 2007 during an ABC debate, and Congressman Dennis Kucinich still had trouble getting attention.
(SOUNDBITE OF 2007 DEMOCRATIC PARTY PRESIDENTIAL DEBATE)
DENNIS KUCINICH: I've been standing here for the last 45 minutes praying to God you were going to call on me.
(LAUGHTER)
HORSLEY: So Fox News decided to limit the field for its primetime debate to the top-10 finishers in a collection of national polls. Other candidates will have a chance to debate earlier in the day. Sean Spicer of the Republican National Committee concedes splitting the field into varsity and JV camps is not ideal. But, he says, you've got to draw the line somewhere.
SEAN SPICER: I understand. I think if I'm someone in 15th or 16th position, sure, I want to square off against one or two. But that's like me saying, hey, I want to jump in a pool and race Michael Phelps. It's just (laughter) you know, that's not how it works.
HORSLEY: Of course, swim meets can be timed to a fraction of a second. Measuring standings in a political contest is not nearly so precise.
SCOTT KEETER: The difference between two candidates who might be number 10 and number 11 might be a half a percentage point, and that could easily be just a handful of actual people that you interviewed.
HORSLEY: Scott Keeter is a polling expert at the Pew Research Center. He notes the network's reliance on polling comes after some high-profile misses in recent elections.
KEETER: Polling in general is still working pretty well, but we're definitely facing problems.
HORSLEY: The biggest problem pollsters face is the shrinking number of people willing talk to them, typically fewer than 1 out of 10. That's OK, so long as the people who do talk are pretty much the same as those who don't. Think of a poll as a ladle dipping into a pot of soup.
KEETER: Every object in the population, every potato and bean in the soup, has an equal chance of being scooped up.
HORSLEY: But if the people who answer the survey are somehow different from those who don't, if the pollster unwittingly talks to a lot of potatoes and not many beans, you can end up with skewed results. That's what happened in 2012 after the first general presidential debate, when many polls showed a surge in support for Mitt Romney. Douglas Rivers, chief scientist for the YouGov polling company says that was more a reflection of who answered the survey than any big shift in voters' attitudes.
DOUGLAS RIVERS: Obama had a terrible first debate and Democrats didn't particularly want to talk about politics after that, and they were less likely to answer their phone or take a poll.
HORSLEY: YouGov takes a different approach. Instead of trying to reach a random sample of voters by telephone, the company sends online surveys to a large number of people who've agreed to take part, then tries to adjust the results to reflect the broader population. YouGov did a pretty good job predicting results in 2008 and 2012. But like other pollsters, it missed the mark in last year's midterms. Poll results at this stage of the presidential contest may not be ready for primetime, but they will determine Fox's primetime lineup. RNC strategist Spicer has a consolation for candidates who don't make it onto the big stage.
SPICER: I know there's a lot of hype right now, but it's not just about debate.
HORSLEY: Spicer notes Mitt Romney skipped the first televised debate four years ago, and he still wound up as the GOP nominee. Scott Horsley, NPR News, Washington. Transcript provided by NPR, Copyright NPR.
