Trending

We hear a lot about how voting patterns trend. Usually it's about demographics, but there are geographic trends too. Cook PVI is a measurement of how strongly congressional districts lean toward one political party compared to the nation as a whole. In order to make that determination we use the country's voting breakdown by party.

In 2000, the two party vote was Gore 50.3%, Bush 49.7%. Thus, a district where Gore got 55.3% would be D+5. In 2008, the two party vote was Obama 53.4%, McCain 46.6%. Thus, a district where McCain got 48.6% would be R+2.

By comparing the PVIs in 2008 and 2000 we can see which way a district is going. I've excluded Texas, Tennessee, Illinois, Hawaii, and Arizona, as these states had home state bounces for the candidates. I also excluded Indiana. The 2008 results were such an outlier of other results that I believe they're misleading. Other elections haven't indicated the state is turning blue.

This is a chart of California districts which are moving Democratic. While there are a lot of them, there are several factors to consider.

1. The change was only 6-7 points over two elections, the bare minimum to be considered trending.
2. Most of these districts are Safe Democratic. It doesn't help to become safer.
3. The districts have been changed so much that the current district might not have nearly the trend.

We do know that Herger and Campbell were moved to safer districts. McNerney and Capps are now in competitive districts. This may indicate a trend, but some of the new area might be trending the other way.

There are a lot of overwhelming numbers here, mostly 6-8 points. North Dakota and Montana have been trending Democratic, and that might bode well for Democrats as both districts will be open in 2012. Most of the rest of the Republicans were moved to safer districts. So the opportunity might not be there. The OR-1 movement likely indicates Democrats will hold this district in the special election.

This group contains seats moving Republican that are in the south, Ozarks, and Appalachia, all areas that have been talked about as trending. The good news for Democrats is that the districts aren't trending as fast on local races. Still, the districts will likely catch up to the Democrats in the next few years.

This is an interesting and sup rising group. We see that there was a heavy concentration in Massachusetts and the New York metro. It includes 6 of the 9 districts that aren't majority minority. Two of the three other districts are just off this list. This is why Republicans were able to win the NY-9 special (It moved 17 points!) and why the GOP should make sure the redistricted New York metro to have as many competitive districts as possible.

Six of the ten Massachusetts districts are on here and two others are just off this list. As with New York, one of the ones that isn't is majority minority. There figures to be opportunity in Massachusetts some time this decade. Since the Democrats hold all the seats any one that does will be one that presents a Republican opportunity.

Two Palm Beach-Broward, Florida districts are on here. These counties have a lot of people from New York and Massachusetts, so it's possible that some of the people trending Republican have made it down here. The two districts, like New York and Massachusetts, are heavily Jewish. I don't know if this is just coincidence or if it means something. Republicans aren't doing a lot better in heavily Jewish areas around Philadelphia and Los Angeles.

There may be a number of unexpected Republican opportunities some time this decade. The Democrats don't seem to have as many, especially since many of these districts got safer for the GOP.