Competitiveness of United States House of Representatives primary elections, 2012

In reality, only 13 U.S. House of Representative incumbents lost their primary bid in the 2012 primary elections for the House. Of those 13 races, eight of them constituted incumbent versus incumbent battles (due to redistricting). Therefore, in 2012, only five incumbents lost a primary election to a non-incumbent challenger. While 393 incumbents ran for re-election in 2012, only 202 of them, or 51.40%, faced a contested primary in 2012. In other words, 192 districts held contested primaries involving incumbents. Compared to past years, 2012 was much more competitive than in previous years. According to a Ballotpedia study focused on primary competitiveness between 2004 and 2010, only 26.35% of incumbents running for re-election faced a primary in those elections. Therefore, in 2012, the number of incumbents who faced a primary almost doubled from the average challenged incumbents in the previous three elections.

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