Finally, after more than 10 months of campaigning from more than a dozen presidential candidates, voters get to weigh in. Iowa Republicans and Democrats will caucus Monday night, and the results could at long last provide some clarity to the Republican and Democratic nominating contests — or not.
Here are five things we're watching:
1. Will the crowds show up to caucus?
How many voters show up Monday night makes a difference. Voting in a caucus is harder than voting in a primary. Iowans have to show up at their caucus site at a specific time and in some cases stay there for a couple of hours. Most analysts and campaign operatives agree that a big turnout benefits the two outsiders — Donald Trump and Bernie Sanders. Lower turnout helps Ted Cruz and Hillary Clinton. Both Trump and Sanders have been trying to expand the universe of Iowa voters by bringing in people who have never caucused before. Trump has a great following with noncollege-educated, white, working-class voters, while Sanders has been reaching out to young voters. Both men lead by double digits with people who tell pollsters they will be participating in their first caucus. But the big question is how many of those first-time Trump and Sanders voters will actually turn out?
The previous turnout record for Republicans was 122,000 votes, set in 2012. If Trump gets a lot of the people who stand in line for hours to get into his rallies to the caucus sites Monday night, that number should be much higher — maybe as high as 150,000.
In 2008, Barack Obama shattered all Iowa records and helped Iowa Democratic turnout reach 240,000. No one is expecting that big a turnout tonight, but Bernie Sanders needs the number to be above the 124,000 that turned out in 2004.
The weather will also be a factor. There's a winter storm predicted to start Tuesday, but it could hit parts of Iowa on Monday night, and that could depress turnout.
2. Does Ted Cruz win Iowa?
The state is tailor-made for Ted Cruz, with lots of conservative evangelical voters. He needs to win it — if he comes in second to Trump, he will have a much harder path to the nomination. And that's why Cruz has been telling his supporters that if Trump wins Iowa, he will be unstoppable. That's because although Trump doesn't need to win Iowa to get the nomination, if he does win, he will have tremendous momentum. He's already ahead 2-to-1 in New Hampshire polls and has leads in all the other early states.
3. Who wins third place?
Marco Rubio has a 3-2-1 strategy: Come in third in Iowa, second in New Hampshire and then win — somewhere. But where? South Carolina? Nevada?
Rubio needs a strong third in Iowa to convince his donors that he has a clear path to the nomination. The Republican establishment would like to coalesce around Rubio as an alternative to Trump or Cruz, but they've been holding back. A stronger-than-expected finish in Iowa would help him consolidate the mainstream wing of the GOP.
If Rubio manages to surge past Cruz and place second in Iowa, he'll be set up to place second to Trump in New Hampshire and become the clear establishment alternative.
4. Does Bernie Sanders have the organization to upset Hillary Clinton?
This is the big question on the Democratic side. Hillary Clinton, stung by her third-place finish eight years ago, built a formidable get-out-the-vote operation. But organization doesn't work without enthusiasm. And the enthusiasm gap favors Sanders, who has excited Democrats with his calls to break up the big banks and make college and health care free.
But Sanders started organizing late in Iowa, and he, like Cruz, really needs to win Iowa. If he beats Clinton in Iowa, it would be an upset, and he'd head into New Hampshire with even more momentum. He already has a big lead there, as neighboring-state candidates usually do (Sanders is from Vermont). A win in both Iowa and New Hampshire for Sanders could change the dynamic in the South, where Clinton has built a firewall based on her support among African-American Democrats.
5. Who will rural Iowa vote for?
This matters for Democrats. Unlike the Republican caucuses, Democrats report delegate totals, not vote totals. And delegates are awarded through a formula based on how candidates do in precincts all over the state. Sanders could be at a disadvantage here because his support has been heavily concentrated in college towns and urban areas, although the Sanders campaign has been trying to expand its reach to rural areas. Clinton's team is filled with Obama field-operation veterans who have built an organization for Clinton that reaches all of Iowa's 99 counties and 1,683 precincts.