How bad is the so-called enthusiasm gap, which predicts that energized Republicans will turn out in droves in November while dispirited Democrats will sit at home? One early indicator: Voter turnout in Republican primaries exceeds that in Democratic primaries for the first time since the 1930s. Nearly 4 million more Republican ballots have been cast than Democratic ballots. However, overall turnout is consistent with where it’s been for the past several midterm elections, with less than 20 percent of the voting-age population participating. Nate Silver at FiveThirtyEight says the main reason for the decline is that closed primaries have made fewer voters eligible.