I think last night's Illinois primary results indicate some difficulties ahead in the state for Democrats that have nothing to do with who the winners and losers were.

Based on the current numbers 885,268 voters were cast in the Democratic primary for Senate compared to 736,137 on the Republican side. Those numbers are awfully close to each other for a state that's overwhelmingly Democratic.

For sake of comparison the last time there were competitive Senate primaries on both sides in Illinois, in 2004 when Barack Obama was nominated, there were nearly twice as many votes cast in the Democratic primary as the Republican one. 1,242,996 voted in the Democratic race to 661, 804 for the Republicans.

Last night's turnout is yet another data point on the enthusiasm gap, showing that Republicans are much more excited about this year's elections than Democrats, even in a deep blue state. We'll have more analysis on last night's results later today...

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.