The Big Questions Looming Over the Iowa Caucuses: Here’s What to Expect

It may feel as if there is little suspense over who is likely to win the Republican presidential caucuses in Iowa on Monday.

But in Iowa, the unexpected can be the expected and a win is not always a win. The result could shape the future of the Republican Party at a time of transition, and the future of the Iowa caucuses after a difficult decade. It could help determine whether Nikki Haley, the former U.S. ambassador, presents a serious obstacle to Donald J. Trump’s return to power — or whether Ron DeSantis, the governor of Florida, will be forced out of the race.

Here’s a guide to some possible outcomes and what they mean for the contenders:

All the assumptions about a big Trump night mean that the former president’s biggest opponent may turn out to be expectations — and not his two main rivals on the ballot, Ms. Haley and Mr. DeSantis. Mr. Trump and his campaign have set the bar high. Mr. Trump has run as an incumbent, not even debating his opponents. His aides say they think he can set a record for an open race by finishing at least 12 points ahead of his nearest rival.

And for Mr. Trump, that could be a problem.

“Trump has been polling around 50 percent plus or minus,” said Dennis J. Goldford, a political science professor at Drake University in Des Moines. “If he were to come in at 40, that’s a flashing yellow light. That suggests weaknesses and uncertainty.”

Two forces could complicate Mr. Trump’s hopes for the night. Those same polls that show him heading for victory, the polls he boasts about at almost every rally he does in Iowa, could feed complacency among his supporters. Why come out and caucus — Caucus Day temperatures are projected to reach a high of zero degrees in places — if Mr. Trump is going to win anyway?

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