Ballotpedia:Congressional incumbents and contested primaries between 2004-2012
Therefore, in at least 2/3 of all elections, the race is essentially decided in the primary, since 2/3 of all districts appear to be single-party districts. We then asked the question: how many times does an incumbent face a primary opponent? In essence, how often does an election occur in which the incumbent has a chance of losing?
Ballotpedia conducted this research in part after seeing the 2012 results which showed an extreme lack of general election competition. During the 2012 election, only 30 races (6.90 percent) had a margin of victory of less than 5 percent. Of those 30 races, 18 were Democratic winners while 12 were Republican. Overall, 285 races (65.5 percent) had a margin of victory of greater than 20 percent. Of those 285 races, 145 were Democratic winners while 140 were Republican.
In other words, most races are anti-climactic in the general election. If the general election is often a foregone conclusion, how competitive are primaries for incumbents? How often are incumbents challenged?
The answer is not very often. In the races we studied, incumbents faced a primary only 31.60 percent of the time. Candidates appear to be realizing this trend, as the rate of primary challenges has increased in recent elections. Notably, the percentage of incumbents facing primary challenges doubled in 2012 from the 2004-2008 level.
In the past five elections, a total of 1,943 races took place where a U.S. House incumbent ran for re-election. In those 1,943 instances, that incumbent faced a primary in 614 occurrences -- only 31.60 percent of the time. In the remaining 1,335 races (68.71%) the incumbent did not face a primary opponent.
The trend does appear to be changing, as 202 of the 393 incumbents (51.40%) who sought re-election did face a primary challenge in 2012. That figure is almost double that of the average for the four preceding elections, which was a very low 26.3% (412 out of 1565).
The table below lists an overview of the figures of each year.
|Did the US House incumbent face a primary opponent?|
|Total||% incs running||Total||% incs running||Total||% incs running||Total||% incs running||Total||% incs running|
|Did not run||42||35||32||28||31|
Obtaining election results for the general election is an easy (albeit time-consuming) task -- the official U.S. House Clerk website lists detailed election results dating back to 1920. However, this report is centered on primaries -- and no current site aggregates all primary results.
Ballotpedia staff used official primary results from the official websites of all 50 states in order to examine election histories from 2004-2012.
We looked for two basic possibilities
- Did the incumbent run for re-election?
- If running, is the incumbent facing a primary?
We did not adjust the findings to reflect the redistricting changes of the 2012 election.
Full tables of results
The following four tables below (click the tabs) show the district by district results for each year. The first three tables display results with only 1 variable. The fourth table combines all three variables.
- Districts in which the incumbent ran but did not face a primary challenge
- Districts in which the incumbent ran and did face a primary challenger
- Districts in which the incumbent did not seek re-election
- All three variables combined.
- Incumbent Did Not Face Primary
- Incumbent Faced Primary
- Incumbent Did Not Run For Re-Election
- All Datasets Combined
This table highlights the districts in which an incumbent ran for re-election but did not face a primary challenge.
This table highlights the districts in which an incumbent ran for re-election and did face a challenger in the primary.
This table highlights the districts in which the incumbent did not seek re-election.
This table highlights all districts, combining the previous three tables.
- United States Congress elections, 2014
- United States Congress elections, 2012
- United States House of Representatives