There’s a lot of talk about why (and how) Donald Trump is leading the GOP polls going into this Thursday’s first debate. A new survey from Monmouth University has Trump at 26 percent, more than double second place, Jeb Bush with 12.2 percent, and third place, Scott Walker with 11.1, well within the margin of error. It’s really tempting to say polls clearly don’t matter since, after all, Donald Trump is currently in the lead. Besides, even though Mitt Romney eventually won the nomination the last time around, nearly every other candidate pulled ahead of him and then fell behind him at some point. So is there really much that we can learn from pre-primary polls?

Nate Silver found some interesting trends with polling data in the run up to the last GOP primary in 2011. Looking at Democratic primaries going back to the 1970s, he found that if you look at the year before the primary votes, it was hard to find any pattern between polling and who eventually won. In 2000 Al Gore led Bill Bradley by 54.2 to 21.1 percent and of course won the nomination. But at the same point in 1991 future president Bill Clinton was polling at 1.7 percent to Mario Cuomo’s 20.7.

But the Republican Party is much less erratic. Silver found that for six of the seven previous primaries whoever led the polls a year before the election wound up taking the nomination. Apparently after that previous window, polls are mostly garbage. They stop being garbage the day before a vote actually happens though, at which point voters seem pretty settled on what they’re going to do. On average a poll conducted the day before the election predicts the final difference between two candidates with a four point margin of error. For the 2012 primaries, FiveThirtyEight and Real Clear Politics had average errors of 2.8 and 4.4 respectively for polls conducted the day before a vote. Go back a week, though, and the average error changes to 13.8 and 12.9 respectively. So imagine the margin of error for polls conducted more than a year before the vote.

Who was polling highest in the first half of 2011? Mitt Romney. And who was leading the polls for the first half of this year, before Trump jumped in with his rapist Mexicans comments? Jeb Bush. Obviously there are a lot more moving parts than this, and every election seems more exceptional than the last according to the news, but Bush eventually winning the nomination fits the pattern of the polls.

For that to happen organically (instead of, say, Trump just burning his bridges to every last voter) Trump would need to run out of momentum and let less luxurious, more tortoise-like candidates overtake him. That seems to suggest Bush, but Amy Davidson at The New Yorker thinks Scott Walker could take the baton next, arguing Bush’s edge in fund raising isn’t a huge advantage when there are fewer restrictions on how much money candidates can get or from where. Either way, history suggests the candidate who makes a quick splash doesn't usually have the ability to maintain it through primaries.

There’s also another way to look at this: If 26 percent of people polled favor Trump to win, then 74 percent don’t. Trump isn’t a usual primary candidate, so if, say, Marco Rubio dropped out it’s likely his supporters would move to Bush or Walker or Ted Cruz or any of the other candidates who aren’t Trump. And despite the interesting trends put together by Silver, a better indicator is the number of endorsements the candidate gets from party leaders. That, more than polls, is a way to gauge how many delegates the candidate will get—and there’s a resounding feeling that those GOP leaders don’t exactly support the Donald.

So this first debate matters quite a bit to the candidates who want to take down Trump (and also Bush). That’s probably why Mike Huckabee tried to up his own crazy leading up to Fox News announcing the roster. Bobby Jindal tried the same thing in Louisiana, first announcing the state would investigate claims Planned Parenthood was selling fetal tissue, then deciding that was too measured to make him popular and instead just pulling all state funding to Louisiana’s two non-abortion performing clinics.

With the debate roster set the other candidates can’t afford to ignore Trump just because he’s so volatile. He claims he’s going to be “very nice & highly respectful” during the debate, but he also doxxed Lindsey Graham, so who the hell knows? Even the Fox News anchors moderating the debate are struggling to deal with Trump, telling Politico they’ve been working on a plan in case he gets out of line, though Megyn Kelly refused to disclose what exactly they have in mind. Bush has been sequestered and prepping for a month now and is expected not stoop to Trump’s level. It’s in his best interest to let Trump lose momentum on his own, but the other candidates face harder roads and might try louder, riskier strategies to stand out. After all, the propecy of the polls is not only working against Trump—it's also working against them.