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Competitiveness is the biggest difference between Texas House elections and those for Texas seats in Congress or in the state Senate.

Adeptly drawn political maps have kept most congressional and Senate seats in the hands of the parties that have them now — a huge advantage for Republicans in the state. But a dozen or so seats in the Texas House remain within the grasp of either of the major political parties, and those are likely to be some of the hardest-fought races in the 2018 general election.

In a dozen districts — six held by Republicans, six by Democrats — the average results in the last two statewide elections was under 10 percent. In each of those, Republican candidates did better overall in 2014 than in 2016 — better, in other words, in a gubernatorial year than in a presidential year. But with Trump’s first mid-term election underway, districts with histories of close elections will be getting extra attention from both parties: Incumbents will need stronger defenses, and challengers might be first in line for resources.

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State Rep. Philip Cortez, D-San Antonio, has the pleasure of serving in the most competitive House district in Texas. The average distance between Republicans and Democrats in the 2014 and 2016 elections was less than one percentage point. It was a slightly Republican district in 2014, a slightly Democratic district in 2016. In other words, it’s a classic swing district.

Clinton beat Trump in ten districts with Republican incumbents in the Texas House. In 2014, Republican Greg Abbott defeated Democrat Wendy Davis in each of those ten districts.

Still, several of those districts are best described as purple, rather than as red or blue. Republican state Reps. Sarah Davis of West University Place, Rodney Anderson of Grand Prairie, Matt Rinaldi of Irving, Cindy Burkett of Sunnyvale, Tony Dale of Cedar Park and three from Dallas — Linda Koop, Morgan Meyer and Jason Villalba — are all in that bunch.

Trump didn’t win in any House districts with Democratic incumbents. But Abbott won in four, each of which belong on the list of purple districts: Cortez, Joe Moody of El Paso, Mary Ann Perez of Houston and Victoria Neave of Dallas. In House District 34, where Abel Herrero of Robstown is the incumbent, Abbott and Davis came to a virtual tie in 2016 (Davis won by two votes out of almost 25,000 cast).

The statewide Republican-Democrat margins were under ten percentage points in only nine districts in 2014, the last gubernatorial election in the state. All nine are currently held by Democrats. The Republicans who made it onto the purple list all made it, in other words, because their party didn’t perform as well with Trump on the ticket in 2016.

That’s one source of hope for Texas Democrats, and a source of worry for Republicans: If the 2018 election is about Trump — not an uncommon idea in a presidential mid-term — it could drag purple districts into the blue end of the political spectrum.

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Here’s the full spreadsheet of these election results for all 150 Texas state House districts, or you can download a version (congressional districts are here, and Senate districts are here).

Behind the numbers

  • The 2016 averages include only the statewide races that had both Democratic and Republican contenders: president; railroad commissioner; Texas Supreme Court, places 3, 5 and 9; and Texas Court of Criminal Appeals, places 2, 5 and 6.
  • The 2014 averages include only the statewide races that had both Democratic and Republican contenders: U.S. Senate; governor; lieutenant governor; attorney general; comptroller; land commissioner; agriculture commissioner; railroad commissioner; Texas Supreme Court, chief justice, places 6 and 7; and Texas Court of Criminal Appeals, place 3.
  • Third-party and write-in candidates were not included in the averages. The raw numbers for election results by political district are available online from the Texas Legislative Council; the computations were done by the author.
  • These are results from the last two general elections and are not predictions or forecasts of what might happen in the 2018 elections.

Read related Tribune coverage:

  • The months leading up to Monday's candidate filing deadline were full of talk about who might challenge whom, a drawn-out round of punditry. Now we know who filed for what, and some of the results were unexpected. [Full story]

  • It's not that Texas Democrats can't find anyone to run for governor in 2018. It's that none of the eight contenders (so far) is familiar to voters across the state. [Full story]

  • A half-dozen members of the Texas congressional delegation have already given up their seats — and the elections haven't even started yet. This cycle could see more changes than a redistricting year, when disruption is the norm. [Full story]

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