Seats without incumbents on the ballot are 56 percent more likely to be Republican than Democratic since 2002

When 14-term Democratic Congressman Alan Mollohan (WV-01) was defeated by primary challenger Mike Oliverio last Tuesday, his district was added to an increasingly long list of districts in which the incumbent will not be on the ballot in November’s general election.

Mollohan’s ousting means there will be at least 38 congressional districts without incumbents in the general election – already the second highest number since new district lines and reapportionment took effect in 2002 (39) with more incumbents still likely to fall (more than 40 states have not yet had their primaries as of this writing).

A Smart Politics analysis of congressional elections over the past decade finds that incumbents have been left off the general election ballot due to retirement from their seats (171), defeat in the primary (11), or expulsion (1) in an average of 8.4 percent of U.S. House districts since 2002 (183 out of 2,175 contests).

Overall, 39 districts were incumbent-free in 2002 (excluding 12 newly created districts after reapportionment), with 37 in 2004, 33 in 2006, 36 in 2008, and 38 to date in 2010.

Republican incumbents have been much more likely to fade away – with 10.5 percent of GOP districts (111 of 1,059 contests) running without an incumbent since 2002. Only 6.4 percent of Democratic incumbents (71 of 1,110) have done so during the last five election cycles.

Overall, seats without incumbents on the ballot have therefore been 56 percent more likely to be Republican than Democratic since 2002.

Republicans have also not sought their U.S. House seat due to retirement (or seeking higher office) in much higher numbers than Democrats.

Of the 171 instances in which a seat was open (or vacant) on Election Day due to the incumbent’s decision to step aside from his or her seat, 108 districts (63.2 percent) were held by Republicans, with just 62 (36.3 percent) by Democrats and 1 independent.

And although many D.C. analysts are projecting a Republican tsunami in 2010, one distinguishing feature of this year’s congressional elections is that Democrats are not running for the hills quite like the GOP did when the Democratic tsunamis hit in 2006 and 2008.

In 2006 and 2008, 10.7 percent of Republican incumbents (46 of 431 seats) did not seek reelection. However, only 6.6 percent of Democratic incumbents (17 of 257) have voluntarily stepped aside from their seats during the 2010 cycle.

Number of Districts by Year and Party in Which Incumbents Voluntarily Did Not Seek Reelection, 2002-2010

Party
2002*
2004**
2006
2008
2010
Total
Republican
22
19
21
26
20
105
Democrat
13
17
9
6
17
62
Independent
0
0
1
0
0
1
Total
35
36
31
32
37
168

* Excludes 12 new districts that were created after reapportionment. ** Includes districts in which (Democratic) incumbents were drawn into different districts after the Texas redistricting plan of 2003. Data compiled by Smart Politics.

And while the instances of intra-party ouster are extremely rare in Congressional elections, Democratic incumbents have been defeated in primaries eight times since 2002 (including Mollohan’s last week), compared to just three for the GOP.

And where are these districts located in which incumbents are retiring or getting defeated in primaries?

An examination as to where these incumbent-free districts have popped up over the past decade reveals that some states have had a much higher exodus rate than others.

· New Mexico leads the way with incumbents not appearing on the general election ballot in 26.7 percent of U.S. House races since 2002 (4 of 15, including all three in 2008).

· Tied for second, incumbents have failed to appear on the ballot in Delaware, Maine, New Hampshire, Oklahoma, South Dakota, Tennessee, Vermont, and Wyoming in 20 percent of U.S. House contests.

· Three states with seven seats in Congress – Alabama, Colorado, and Louisiana – have also shed incumbents at more than twice the rate of the national average (17.1 percent).

· Four states, meanwhile, have had incumbents on the ballot in each general election since 2002: Connecticut and three states with at-large Representatives (Alaska, Montana, and North Dakota).

· Florida, which has the fourth most congressional districts in the nation with 25, has had the largest number of districts in general election contests without incumbents with 14, followed by Texas (11), Tennessee (9), Ohio (9), California (9), Georgia (8), and New York (8).

Of course, these numbers are subject to change if more incumbents – Democratic or Republican – share the same fate as Alan Mollohan in the coming months.

Number of Districts in Which Incumbents Did Not Appear on the General Election Ballot by State, 2002-2010

State
’02
’04
’06
’08
’10
Total
%
New Mexico
1
0
0
3
0
4
26.7
Delaware
0
0
0
0
1
1
20.0
Maine
1
0
0
1
0
2
20.0
New Hampshire
1
0
0
0
1
2
20.0
Oklahoma
2
1
1
0
1
5
20.0
South Dakota
1
0
0
0
0
1
20.0
Tennessee
3
0
2
1
3
9
20.0
Vermont
0
0
1
0
0
1
20.0
Wyoming
0
0
0
1
0
1
20.0
Alabama
3
0
0
2
1
6
17.1
Colorado
1
1
2
2
0
6
17.1
Louisiana
1
3
0
1
1
6
17.1
Arkansas
0
0
0
0
3
3
15.0
Kansas
0
0
0
0
3
3
15.0
Nebraska
0
1
1
0
0
2
13.3
South Carolina
1
1
0
0
2
4
13.3
Utah
1
0
0
1
0
2
13.3
Georgia
3
3
1
0
1
8
12.3
Florida
2
2
4
1
5
14
11.2
Arizona
1
0
1
1
1
4
10.0
Hawaii
0
0
1
0
0
1
10.0
Idaho
0
0
1
0
0
1
10.0
Maryland
1
0
1
2
0
4
10.0
Mississippi
1
0
0
1
0
2
10.0
Ohio
2
0
4
3
0
9
10.0
Rhode Island
0
0
0
0
1
1
10.0
Michigan
2
1
1
0
3
7
9.3
Missouri
0
2
0
1
1
4
8.9
Iowa
1
0
1
0
0
2
8.0
Minnesota
0
0
2
1
0
3
7.5
Illinois
1
1
2
2
1
7
7.4
Pennsylvania
2
3
0
1
1
7
7.4
Texas
2
8
1
0
0
11
6.9
Indiana
1
0
0
0
2
3
6.7
Kentucky
0
1
0
1
0
2
6.7
Nevada
0
0
1
0
0
1
6.7
Washington
0
2
0
0
1
3
6.7
West Virginia
0
0
0
0
1
1
6.7
New Jersey
1
0
1
2
0
4
6.2
New York
0
2
2
4
0
8
5.5
Wisconsin
0
0
1
0
1
2
5.0
North Carolina
1
2
0
0
0
3
4.6
Oregon
0
0
0
1
0
1
4.0
Virginia
0
1
0
1
0
2
3.6
California
2
2
1
2
2
9
3.4
Massachusetts
0
0
0
0
1
1
2.0
Alaska
0
0
0
0
0
0
0.0
Connecticut
0
0
0
0
0
0
0.0
Montana
0
0
0
0
0
0
0.0
North Dakota
0
0
0
0
0
0
0.0
Total
39
37
33
36
38
183
8.4

Through May 16th. Notes: Last column indicates the percentage of general election contests since 2002 in which incumbents did not appear on the ballot in that state. Excludes 12 new districts that were created after reapportionment in 2002. Includes districts in which (Democratic) incumbents were drawn into different districts after the Texas redistricting plan of 2003. Data compiled by Smart Politics.

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