You can tell a lot about the Democratic and Republican electorates by looking at who's planning to vote in next year's primaries and caucuses. And when you look at where those people live a few points emerge: One, the geography of Democratic and Republican primary voters is sharply different and two, the differences seem to equal an advantage for Democrats.
The American Communities Project examined self-reported Democratic and Republican primary-voter data from the last three NBC News/Wall Street Journal polls (September and October) and looked at where those voters live. The Project then compared the breakdown of those voters' home counties to a breakdown of the 2012 presidential electorate. The numbers are telling.
Look carefully at that table and note the differences.
Among self-reported Democratic primary voters, 49 percent live in Big Cities or Urban Suburbs, dense urban places. That's a little higher than the 2012 general election electorate, wherein 44 percent of the voters came from those big urban places. But note how different the numbers are from the self-reported GOP primary electorate - only 31 percent of those voters come from the Big Cities or Urban Suburbs.
Republican primary voters, meanwhile, are much more likely to come from the counties that make up Rural America and Faith Driven America, less populous more socially conservative counties. Those places hold 30 percent of the GOP primary vote. But they held only 20 percent of the electorate in the 2012 general election. Only 17 percent of Democratic primary voters live in those counties.
Those are some big variances and they have real significance. They explain why the campaigns for the hopefuls in each party look so dissimilar and they illustrate a deeper problem Republicans will likely face next fall.
One of the big problems the GOP has had in recent elections is the Democrats extending their advantage in urban areas. In the 2000 election, Vice President Al Gore, the Democrat, won the Big City counties by 21 points and the Urban Suburbs by 11 points. In 2012, President Barack Obama won the Big Cities by 31 points and the Urban Suburbs by 17 points.
Now look at the numbers in that table once more. What these primary voter numbers really measure is relative engagement - are you more interested in the Republican fight for the nomination or the Democratic fight? And on that measure the Democrats hold a solid advantage in big urban areas.
Furthermore, in a more basic sense, the Democratic primary electorate simply looks more like the 2012 general election electorate than the Republican primary electorate does across most of the groups. For that reason the Democrats' messaging may need less general election tweaking than the Republicans' messaging.
To be clear, the data here aren't definitive for 2016.
It could be that these numbers end up hurting Democrats and helping Republicans. It's possible that those urban areas tune in more seriously to the Democratic primary fight and are turned off. And it could be that the lack of attention in those urban areas helps Republicans because it gives the GOP nominee a chance to reintroduce himself or herself next fall.
But the differences between these electorates tell us the Democratic nominee is likely to be better known and understood in the urban and dense suburban areas that are crucial to winning a general election. And on that score, the Republican nominee is likely going to have some work to do.