The FiveThirtyEight Team Goes To Iowa

DES MOINES — The consensus is that Ted Cruz is more likely to win the Republican Iowa caucus than Donald Trump. The problem for Cruz, of course, is that winning here does not mean that he’s going to win New Hampshire or the nomination (see: Mike Huckabee and Rick Santorum). Indeed, a close look at the polls indicates that Cruz’s coalition is good in Iowa and not good at all in New Hampshire. Cruz has basically no support from moderate Republicans. He earned just 9 percent from Iowa moderates in a Marist poll conducted last week and 7 percent from Iowa moderates/liberals in a Quinnipiac poll out this week. Cruz is doing well in the Hawkeye State because he took 36 percent and 37 percent from conservatives in those surveys, respectively. That could be enough for him to win the caucus given that about 84 percent of caucus-goers in 2012 identified as conservative compared to just 17 percent who were moderate or liberal. But if Cruz’s weakness with moderates and liberals continues in New Hampshire, it will likely doom him there. Why? Moderates and liberals made up 47 percent of New Hampshire primary voters in 2012. That means Cruz would do about 10 percentage points worse in New Hampshire even if he got the same support from each ideological group there that he currently gets in Iowa. Donald Trump’s Iowa coalition, on the other hand, is far better suited for New Hampshire. Trump was at 28 percent among moderates in the Marist survey and 37 percent among moderates and liberals in the Quinnipiac poll. Trump isn’t doing too badly among conservatives either, with 21 percent and 28 percent in those polls, respectively. This ideological split helps to explain why Trump is currently close to 30 percent and leading in the New Hampshire polls while Cruz is well back with closer to 10 percent.