GOP Challengers Close Historical Gap But Fall Short in Texas US House Primaries

Tea Party candidates cut into Republican incumbents' victory margins by levels not seen in at least a generation

While there were no upsets in the Republican U.S. House races in Texas' primary Tuesday, the increasing presence of the Tea Party continues to be felt, with particular pressure applied on the Lone Star State's incumbents.

A Smart Politics review of nearly 350 Texas Republican U.S. House primary races over the last 20 years finds that the 2012 cycle showed GOP challengers exerting a level of pressure on incumbent U.S. Representatives unseen in at least a generation.

While all 22 Republican incumbents easily won reelection Tuesday, their victory margins were substantially lower than previous cycles.

From 1992 through 2008, the 119 GOP incumbents saw their general election ticket stamped by an average victory margin of 91.9 points in the primaries - including dozens of candidates who ran without opposition.

In 2010 - the first primary after the formation of the Tea Party - the margin of victory for the 20 Republican incumbents on the ballot dropped noticeably to an average of 80.3 points.

In 2012, that number dropped even further with the state's 22 GOP incumbents winning by an average of 67.7 points - or 24 points lower than the nearly two-decade long average before the Tea Party's formation from 1992 through 2008.

The Tea Party has affected the incumbent's numbers across the board.

From 1992 through 2008, only 10 out of 119 incumbents received less than 80 percent of the vote in the primary, and all but three eclipsed at least 70 percent.

In 2010 (four) and 2012 (11), a total of 15 incumbents failed to reach he 80 percent mark, with four failing to hit 70 percent.

On Tuesday, veteran lawmaker Ralph Hall (pictured above) in the state's 4th CD struggled the most, tallying 58.3 percent and winning by 37.3 points.

Other incumbents failing to reach the 80 percent mark were Joe Barton in the 6th CD (63.2 percent), Kevin Brady in the 8th (76.1 percent), Mike Conaway in the 11th (70.4 percent), Mac Thornberry in the 13th (78.3 percent), Randy Neugebauer in the 19th (74.3 percent), Lamar Smith in the 21st (76.6 percent), Pete Olson in the 22nd (76.5 percent), Kenny Marchant in the 24th (67.9 percent), Blake Farenthold in the 27th (71.4 percent), and John Carter in the 31st (76.0 percent).

The average incumbent vote Tuesday of 82.0 percent dropped 13.3 percent from the 94.6 percent average compiled during the previous 10 election cycles from 1992 through 2010.

Texas Republican U.S. House Incumbents Performance in Primaries by Cycle, 1992-2012

Not surprisingly, the sheer number of Republican candidates challenging GOP incumbents has skyrocketed in Texas during the last two cycles.

From 1992 through 2008, just 39 candidates challenged the 119 Republican incumbents in U.S. House primaries, or 0.33 opponents per incumbent.

In 2010 and 2012, the challenger rate more than tripled, with 46 challengers for the 42 incumbents running for reelection, or 1.10 opponents per incumbent.

The rate has held steady during the Tea Party cycles of 2010 (1.10 per incumbent) and 2012 (1.09).

Texas Republican U.S. House Primary Challengers, 1992-2012

A key component to chipping away at the average vote tally of Republican incumbents during the 2010 and 2012 primaries has been giving fewer and fewer officeholders a free ride to the general election.

From 1992 through 2008, only 28 of 119 GOP incumbents in Texas faced a primary challenger, or 23.5 percent.

That number increased to 11 of 20 in the 2010 cycle (55.0 percent) and 16 of 22 this cycle (72.7 percent).

Only Louis Gohmert (TX-01), Ted Poe, (TX-02), Jeb Hensarling (TX-05), Quico Canseco (TX-23), Michael Burgess (TX-26), and Pete Sessions (TX-32) ran without opposition Tuesday on the Republican side of the ballot.

Percentage of Unchallenged Texas Republican U.S. House Incumbents, 1992-2012

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