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What’s At Stake For Republicans In The March 15 Primaries

This could be it, folks. The Republican presidential primary may be settled — or at least a lot clearer — on Tuesday. Republicans will vote in six contests. Donald Trump is looking to stay on track to win a majority of states, if not delegates. Marco Rubio and John Kasich could be making their last stands. And Ted Cruz is hoping he’s in a two-man race with Trump come Wednesday. A lot is at stake, so let’s go through the contests one by one. (Also, check out my preview of the Democratic contests.)

Florida primary


Florida is the biggest prize on Tuesday, and it looks like Trump is going to win it. Despite Rubio calling the Sunshine State home, Trump has led every single poll taken there this year. Trump should do well in the northern part of the state, a culturally conservative region that tends to vote like Alabama and Georgia, where Trump won handily. He should also perform well with older migrants from the Northeast who live in southern Florida. Rubio, for his part, is likely to draw a disproportionate share of his support from the Gold Coast in the southeast. Don’t be surprised if the polls showing a single-digit Trump lead (instead of a double-digit lead) end up being accurate. Cuban voters — who are projected to make up 5 percent to 10 percent of Republican voters in Florida — have historically been difficult to poll, and surveys that don’t properly account for them will be missing Rubio’s core constituency. Still, all the polls have Rubio trailing, and it’s difficult to see how he continues his campaign if he loses his home state.

North Carolina primary


This is the only truly proportional state voting on the GOP side Tuesday, and there is no threshold to qualify for delegates. All of the candidates will win delegates in the Tar Heel State. Trump has led in every survey conducted in North Carolina this year, but his support has varied greatly from poll to poll. Some peg Trump’s support in the low 30s, while one poll from SurveyUSA gave him 48 percent. Given that Trump won only 32.5 percent in the South Carolina primary to the south and 34.8 percent in the Virginia primary to the north, the polls in the lower 30s may be closer to the mark. If Trump doesn’t make it out of the low 30s, Cruz has a chance to win. He has generally polled in the high 20s. Still, I must emphasize that this race is about delegates, and a candidate doesn’t get extra delegates for winning with 32 percent versus losing with 32 percent.

Illinois primary


This is perhaps the most confusing state voting Tuesday. Trump is polling at only about 30 percent to 35 percent in most surveys. But Cruz, Kasich and Rubio are splitting the non-Trump vote, according to the polls. That could potentially make it difficult for the anti-Trump constituency to properly cast the most effective anti-Trump vote. Adding to the confusion: The vast majority of delegates are determined by the vote in each congressional district. Voters in each district elect three delegates directly instead of voting for a presidential candidate (though each delegate’s preferred candidate is listed on the ballot). So, voters need to vote up to four times — once for their candidate of choice in the statewide race and then for each of the three congressional district delegates they prefer. Cruz is probably going to do best downstate, while Kasich and Rubio are more likely to find strength in and around Chicago. Will voters sort through this mess and vote strategically, coalescing behind a single anti-Trump vessel? It’s difficult to say. As long as Trump holds his 35 percent of the vote, he’ll probably win most of the delegates in Illinois in part by taking the 15 delegates awarded to the statewide winner.

Ohio primary


This is Kasich’s last stand. If he doesn’t win, his campaign is over. But Kasich is in a better position to win Ohio than Rubio is to win Florida: Kasich led in two polls released in the past week. Not only that, but Kasich did fairly well in Kentucky and Michigan in the counties bordering Ohio. One wild card in this contest is that Rubio’s communications director basically said that Rubio supporters should vote for Kasich in Ohio to stop Trump. Although Rubio’s numbers have fallen in the state over the past few weeks, any Rubio fans moving into the Kasich column could make a big difference. The importance of this primary to the larger Republican race is difficult to overstate. According to my math (and that of Republican Benjamin Ginsberg, who basically wrote the GOP’s delegate rules), Trump is unlikely to reach a majority of delegates needed to clinch the Republican nomination if he loses Ohio.

Missouri primary

  • 52 delegates (40 district, 12 statewide)
  • Winner-take-all on the district and statewide level

This could be Cruz’s best state on Tuesday, though there has been little polling so it’s hard to know exactly what’s going on in the Show-Me State. As in almost every other state, Trump is leading the field with support in the 30s. But unlike in Illinois, Cruz is in a clear second place in Missouri. Cruz has also done disproportionately well in the region. He won Iowa to Missouri’s north and Kansas to the west, and he came in a close second in Arkansas to the south. Cruz also was competing with Rubio to be the anti-Trump in those states, but with Rubio’s struggles, Cruz will get a clearer shot at Trump in Missouri. That said, those contests were not open primaries, like Missouri’s, a format that has tended to favor Trump. If Trump wins in Missouri, he may be on his way to winning every state on Tuesday. Either way, there’s a good chance of a delegate split in the state because most are awarded by congressional district.

Northern Mariana Islands caucus

Most of you probably don’t think very often about the Northern Mariana Islands, but nine delegates is nothing to scoff at. There’s no polling for this contest, but the smart money is on Trump. Why? The commonwealth’s political apparatus is backing Trump thanks to Ben Carson’s endorsement. The executive director of the commonwealth’s Republican Party had been a member of Carson’s campaign and just signed up with Trump’s team. Trump also has the support of the commonwealth’s governor, Ralph Torres. If the voters follow their elected leaders, Trump is a shoo-in. (Then again, voters haven’t done a lot of following their leaders this campaign.)

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Harry Enten was a senior political writer and analyst for FiveThirtyEight.