Speculation abounds that rogue Democrats turned out for Tea Party upstart Dave Brat, and helped lift his campaign to victory in the Republican primary. One Virginia Democrat even claimed local Democratic committees orchestrated a whisper campaign to mobilize their voters for Brat, hoping a Cantor loss might rework the dynamics of the general election in their favor.
What, then, are the odds Democrats voted in sufficient numbers to defeat Cantor? Rather low.
The question is one of turnout. Turnout in the 7th's primary election surpassed 60,000, far more than any other House primary in the state. Brat beat the incumbent Cantor by some 7,000 votes, or 11 percentage points, in a district which stretches from the Richmond suburbs in the south to rural Culpeper in the north, and includes portions of the Shenandoah Valley.
The largest increase in turnout came in ultra-conservative Hanover County, where Brat ran up his largest margin of victory. Mitt Romney carried the county in 2012 with 67 percent of the vote. Brat too collected 67 percent in Hanover and defeated Cantor by some 4,500 votes (by far the largest margin of any county.) As Brat's final margin of victory in the district was slightly more than 7,000 votes, the 4,500-vote margin in Hanover County rendered Brat's lead insurmountable.
This fact is decisive in debunking the argument Democrat defectors helped Brat. If this were in fact the case, we would not expect to see a significant increase in turnout in the district's most conservative county, doubly so since that county was more than half Brat's margin of victory. Hanover's largest town, Ashland, is home to Randolph-Macon College, where Brat is a professor of economics.
If Democrats turned out for Brat, we would expect increased margins of victory for Brat in the precincts which host large numbers of Democrats, in this case the parts of Henrico and Chesterfield counties that are in the 7th District. Each includes significant suburban populations. And in fact, both Henrico and Chesterfield went for Brat Tuesday night, 53-47 and and 55-45 respectively. Approximately half of his total votes came from these precincts.
However, this does not suggest Democrat shenanigans were at work. Brat's performance in each county is consistent with his performance in other counties he won. Additionally, as Michael McDonald of the U.S. Election Project points out, Cantor performed better in Henrico County's most Democratic precincts compared to his district-wide totals. If Democrats turned out for Brat, we would expect the inverse to be true.
The primary betrays seismic shifts in the Richmond suburbs which portend not just the end of Cantor's career in Congress, but an ideological reorientation of the Virginia Republican Party. It does not indicate Democrats wrought chaos in this election.