The action this year is supposed to be on the Republican side of the partisan divide, with Tea Party activists and anti-Obama enthusiasts crowding GOP primaries to get a head start on the big push toward November.

Democrats, we are told, are supposed to be discouraged, disenchanted and disengaged.

There’s just one problem with that calculus:

The actual numbers.

In the May 18 primaries — the most intensely covered so far in this election season — voters went to the polls in four states with crowded Democratic and Republican primary ballots. In every one of the states, there was a clear enthusiasm gap.

But it wasn’t on the Democratic side.

The Republicans side was where the turnout dropped off.

In Kentucky, where virtually all the national media attention was on the Republican U.S. Senate primary, where insurgent Rand Paul drew Tea Party backing and upset the GOP establishment after a brutal battle, almost 352,000 Republican primary ballots were cast. But there was also a Democratic Senate primary, and more than 520,000 votes were cast in it.

In Oregon, where the hottest action in races for the gubernatorial and U.S. Senate nominations was on the GOP side, and where Tea Party activism was at a fever pitch, roughly 326,000 Republicans cast primary ballots. But roughly 387,000 voted in the Democratic primary.

In Pennsylvania, where both Democrats and Republicans nominated candidates for governor from multi-candidate fields and where there were primaries on each side of the ballot for U.S. Senate nominations and down-ballot positions, more than 1,045,000 Democratic primary ballots were cast. Barely 820,000 Republican primary votes were recorded.

In Arkansas, where both parties nominated U.S. Senate candidates, and where Republicans are supposedly surging, the turnout for the 8-way Republican primary is expected [when all the votes are counted] may reach 450,000. But the total for the three-way Democratic primary will easily exceed 325,000.

And Arkansas hasn’t even settled the race. Democratic voters will return to the polls in June to decide a run-off race that could see a senior senator removed from office.

 There point here is not to suggest that one party or the other has a corner on electoral enthusiasm this year.

The point is that, if we believe the numbers, there is more enthusiasm on the Democratic side than the Republican.