The Partisan Makeup of NH House Districts

The next (and last?) chapter in my look at the partisan makeup of New Hampshire voters is a study of the 103 districts for the state House of Representatives. This is a follow up to earlier looks at the voting wards and the state Senate districts.

I’ve calculated the Partisan Voting Index (PVI) for each House district. (See the voter ward diary for a discussion of the Cook PVI and methodology.) As the map shows, 44 of the 103 districts, representing 150 House seats, lean Democratic (D+3 PVI or more). The most Democratic district in the state is Grafton-9 (D+28 PVI) which includes Hanover and Lyme. 26 districts, representing 133 seats, lean Republican (R+3 PVI or higher). The most Republican district in the state is Bedford’s Hillsborough-18 (R+12 PVI). And 33 districts, representing the 117 House seats that will determine which party holds the majority, are rated even with PVI between R+2 and D+2.

I have also prepared a chart listing each of the 400 House seats with the district’s PVI for 2004 and 2008. To provide an indication of relative voting margin, I calculated the incumbent’s 2008 vote as a percentage of total votes cast divided by the number of seats in the district.

For a discussion of specific House seats and the partisan makeup of their districts, you should definitely check out Steve Marchand’s work. (His NHPVI is relative to state races rather than relative to the national presidential vote as with Cook PVI. Since Cook PVI rates New Hampshire as D+1.6, Steve’s NHPVI ratings will generally average a point or two more Republican than Cook PVI. He explains his methodology here.) You’ll find the complete set of maps and datasheets here. Enjoy.

Cross-posted to Blue Hampshire

UPDATE: Added scatter plot indicating positive relationship between PVI and House election results.