The exit polls indicate that an unusually high number of voters who participated in tonight's Democratic primary (12 percent) identified themselves as Republicans. What was even more surprising, however, was who they voted for: 75% of Republicans who crossed over to participate in the Democratic primary voted for Hillary Clinton, while only 25% voted for Obama. But perhaps I shouldn't have been surprised, because Rush Limbaugh has been actively encouraging his sizeable and easily duped listening audience to cross over and vote for Hillary in an attempt to drag out the contentious battle between her and Obama. The numbers from Mississippi raise a question: is the unusually high Republican crossover vote an anomaly, or part of a trend that could affect the outcome of the Democratic nomination?
In 21 races that were held prior to Romney ending his campaign on February 7, the average percentage of Republican crossover votes in these contests was 3.52% of all votes cast.* In only 5 of these states was Republican turnout higher than 5%, with the highest being 7% in Oklahoma. Only 6 of the pre-2/7 races had detailed polling data for the Republican crossover vote, but in those states, Obama won a sizeable plurality of the Republican crossover vote in all but one, with an average* of 48% for Obama to 27% for Clinton.
In 6 races that were held after Romney dropped out on 2/7, the average* percentage of Republican crossover votes was 7.5% of all votes cast, more than double the pre-2/7 average. Broken down further, the numbers get even more interesting. In 3 races that were held within a week after Romney dropped out, the average* percentage of Republican crossover votes was 5% of all votes cast, with the highest being 7% in Virginia. But in both the Texas and Ohio races on 3/4, the average* Republican crossover vote increased to 9%. And as stated previously, the crossover vote in tonight's contest was 12%. That gives us an average* Republican crossover vote of 3.71% prior to Rush Limbaugh's appeal, and 10% post-Rush.
And as Republicans have begun to cross over in increasing numbers, Hillary's take of the Republican crossover vote has likewise increased. 5 of the races held from 2/7 to tonight had detailed polling data for the Republican crossover vote. Of those states, Obama won the Republican crossover vote in 3 states, Clinton won it in 1 state, and they tied in 1 state, with an average* of 50.4% for Obama to 42% for Clinton. But 2 of those races were held in the week immediately after Romney dropped out, and before Rush's remarks: in those states, Obama took the plurality of the crossover vote in both states with an average* of 62.5% for Obama to Hillary's 20%. The other 3 were held post-Rush, and in those contests Obama and Clinton both won the Republican vote in 1 state each and tied in 1 state, with an average* of 42.33% for Obama to 56.67% for Clinton, marking a significant swing of the Republican crossover vote in Clinton's favor.