Washington: US presidential candidates have spent months crisscrossing farm fields between the towns and small cities of Iowa, trying to woo voters in the Midwestern state ahead of its long-awaited caucuses on Monday.
Five things to watch for in the nation's first presidential nominating event:
TRUMP'S SURGE OR STUMBLE: With surveys showing Donald Trump dominating his Republican rivals - both nationally and in Iowa - the question has become whether the celebrity billionaire can turn his polling supporters into caucus goers. His closest competitor, Texas Senator Ted Cruz, had led opinion polls in the state until recently and has built an extensive campaign organization designed to actually get his supporters to turn out. The Republican establishment would like to see both Trump and Cruz fail, but analysts have indicated they may seek to first trip up Cruz, who is seen as too hardline and disagreeable, in order to more effectively block Trump moving forward.
THE FIGHT FOR THIRD: There are nine other serious Republican candidates, and many of them will see their 2016 presidential ambitions quickly falter without a strong showing. In later primaries, third place is a letdown; in Iowa, it can be a ticket to survival. Florida Senator Marco Rubio is the top contender for bronze, with the limping campaigns of Ben Carson and Jeb Bush desperate to snatch a consolation prize.
A REPEAT CLINTON DEFEAT?: Hillary Clinton suffered an embarrassing loss to Barack Obama eight years ago in Iowa. Polls indicate that Democratic caucus-goers could once again frustrate Clinton, this time by handing victory to Vermont senator and avowed socialist Bernie Sanders. But even with another Sanders win possible in New Hampshire on February 9, the electoral calendar thereafter favours Clinton.
VOTER TURNOUT: Weather can be an important factor. The most fervent party members caucus, which requires direct participation in evening precinct meetings that can last two hours or more. In fact, most Iowans choose not to participate in what can be a complicated process. The conventional wisdom is that high turnout benefits Trump and Sanders, because it means the two anti-establishment candidates were able to appeal to non-traditional voters - perhaps indicating a trend that could be repeated nationally.
IT'S ACTUALLY ALL ABOUT THE GRANITE STATE: A few Republicans trailing far behind in Iowa are hoping the primary vote a week later in New Hampshire will breathe new life into their campaigns. Ohio Governor John Kasich's momentum is building in the New England state, while New Jersey Governor Chris Christie and Bush are similarly polling stronger there than in Iowa.