Where is the Political Middle Voting this Year?

As I pointed out in a recent post, the idea that there has been a surge in independent voters in the Democratic primaries is not supported by exit poll data. I thought it would be interesting, though, to compare the Republican and Democratic primary electorates to see which party is doing the best job of reaching out to the political middle.

Let's start by comparing the partisan complexion of the primary electorates.


The party electorates are mirror images of each other. About 76% of the votes in each of the parties' primaries have come from their own partisans, 20% from independents and around 4% from the other party. The bottom line is that neither party is doing a better job attracting independents or rival partisans. Once again, this finding is a bit at odds with the common perception that the Democrats have been more successful at drawing independent voters.

But party identification is just one way of slicing the electorate. What about the ideological middle? Which party has been most successful at reaching out across ideological lines?

Here, the picture is much less balanced. The Republican primaries are dominated much more by conservatives than the Democratic primaries are by liberals; Democrats have done a better job attracting moderates than Republicans have; and Democrats have had somewhat more successful attracting conservatives than the Republicans have had attracting liberals.

So the general picture is that both parties' primaries have been dominated by their respective partisans, but the Democratic primaries have been more ideologically heterogeneous than the Republican primaries.

Does this pattern auger well for the Democratic nominee, whomever s/he might be, in the general election? I suppose it does if it reflects the breadth of appeal the nominee will have to the November electorate--but that might depend on who the nominee is.

Note: These data are based on averages across those states for which exit poll data are available.