Hillary Clinton barely beat Bernie Sanders in Iowa. It was basically a tie. Her 0.3 percentage point margin ranks as the thinnest victory in Iowa Democratic caucus history.
But it’s likely that Clinton was ahead by a wider margin in the initial preferences of caucus participants.
Iowa Democrats don’t report the preferences of voters as they enter the caucuses. Instead, voters are allowed to change who they support after a first round of voting. Sometimes there are multiple rounds, after which candidates who don’t clear a viability threshold are eliminated. Even after all that shuffling, we don’t get a raw vote total. Instead, we get “statewide delegate equivalents.” Those are the results you saw Monday night. And as I wrote earlier Monday, sometimes the difference between the percentage of statewide delegate equivalents won and each candidate’s initial share of the vote is greater than 5 percentage points.
Sanders appears to have benefited from this process Monday night.
According to the initial preferences extrapolated from data from 58 sample precincts collected by Edison Research, Clinton won an estimated 49 percent, Sanders 46 percent and Martin O’Malley 3 percent; 2 percent were uncommitted. In statewide delegate equivalents, Clinton earned 49.85 percent, Sanders 49.58 percent and O’Malley 0.54 percent; 0.03 percent were uncommitted. When you look at the differences between those sets of percentages, all but Clinton’s were outside the margin of error.
The simplest (and probably correct) conclusion to draw from the data is that O’Malley supporters and Iowans who were initially uncommitted disproportionately chose Sanders as their second choice. Although there is no entrance poll data asking about reallocation, there are anecdotal reports of O’Malley backers going to Sanders. Additionally, some pre-election surveys suggested that O’Malley voters were more inclined to pick Sanders than Clinton as their second choice.
Those additional backers nearly eked out a victory for Sanders.
The problem for Sanders is that he didn’t win and so didn’t receive what probably would have been a very favorable wave of media coverage. Sanders needed that press because Iowa’s Democratic caucus electorate, being very white and very liberal, is among the most Sanders-friendly electorate in the country (although New Hampshire is even friendlier): A tie in Iowa implies that he would lose in most other states.
On the other hand, the Iowa caucuses are just the beginning of the process. Sanders will have opportunities to expand his base as the primary season goes forward.
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