Nate Silver of FiveThirtyEight.com whose prediction's of elections is dead on gives his take Trump's chances after first ballot. At the prediction market Betfair on Friday morning, bettors put Donald Trump’s chances of winning the Republican presidential nomination at 56 percent. That’s down a fair bit — Trump had been hovering at about 70 percent after his win in Arizona (and loss in Utah) last week. Meanwhile, the likelihood of a contested convention according to bettors has considerably increased. There’s now a 63 percent chance1 that the convention in Cleveland will require multiple ballots, according to Betfair. In other words, the markets are now betting on a contested convention. Not just a near-miss, where the nomination is resolved at some point between the last day of GOP primaries June 7 and the start of the convention July 18, but the thing that political journalists dream about: a full-blown contested convention where it takes multiple ballots to determine the Republican nominee. Here’s the thing, though: Those markets don’t make a lot of sense. If you really think the chance of a multi-ballot convention is 63 percent, but also still have Trump with a 56 percent chance of winning the nomination, that implies there’s a fairly good chance that Trump will win if voting goes beyond the first ballot. That’s probably wrong. If Trump doesn’t win on the first ballot, he’s probably screwed. The basic reason is simple. Most of the 2,472 delegates with a vote in Cleveland probably aren’t going to like Trump. Let’s back up a bit. In most of our discussions about delegates here at FiveThirtyEight, we treat them as though they’re some sort of statistical unit. We might say a candidate “racked up 44 delegates” in the same way we’d say Steph Curry scored 44 points. But those delegates aren’t just a scoring mechanism: Delegates are people, my friends. Delegates are people! And as I said, they’re mostly people who aren’t going to like Trump, at least if the excellent reporting from Politico and other news organizations is right. (If Trump turns out to have more support among GOP delegates than this reporting suggests, even marginally, that could end up mattering a great deal.) How can that be? In most states, the process to select the men and women who will serve as delegates is separate from presidential balloting. In Massachusetts, for instance, Trump won 49 percent of the GOP vote on March 1 — his highest share in any state to date — to earn 22 of the state’s 42 delegates. But the people who will serve as delegates haven’t been chosen yet. That will happen at a series of congressional district conventions later this month and then a Republican state meeting in May or June. According to Politico, most of those delegates are liable to favor Ted Cruz or John Kasich rather than Trump. Twenty-two of them will still be bound to Trump on the first ballot, but they can switch after that. The same story holds in a lot of other states: in Georgia, Louisiana and South Carolina, for instance — also states that Trump won.