Factbox-Key federal and state races to watch in Tuesday's Texas primary

By Joseph Ax

(Reuters) -Texas held the United States' first primary nominating contests of 2022 on Tuesday, eight months before the midterm elections that will determine control of the U.S. Congress as well as the governors of 36 states.

Under Texas law, if no candidate earns a majority of the vote in any given election, the two top finishers head to a runoff on May 24. Here are some key races to watch:

ABBOTT, O'ROURKE FACE NOVEMBER MATCHUP

Republican Governor Greg Abbott handily fended off two more-conservative challengers, former Texas Republican Party Chairman Allen West and former state Senator Don Huffines. That sets up a Nov. 8 contest with former U.S. Representative Beto O'Rourke, who had faced no serious competition for his party's nomination.

WILL PAXTON SURVIVE?

Texas Attorney General Ken Paxton has already won one reelection campaign since his indictment in 2015 on state securities fraud charges. This time around, he is headed to a May 24 runoff against state Land Commissioner George P. Bush, the grandson of former President George H. W. Bush, according to television network projections.

TRUMP LOYALTY TEST

Republican Representative Van Taylor comfortably won a second term in Texas' 3rd District in 2020, even though Trump barely outperformed Biden in the district. But Taylor's vote to support the creation of an independent commission to investigate the Jan. 6, 2021, assault on the U.S. Capitol by Trump supporters has attracted Republican opponents who accuse him of betraying the former president and his party.

After redistricting, the suburban Dallas district is significantly more conservative in 2022, potentially making Taylor vulnerable to a challenge from the right. His leading rival is Keith Self, a former judge in Collin County who has attacked Taylor for his vote, even though the measure failed in the Senate. House Democrats have launched their own Jan. 6 probe.

A SUCCESSOR TO KEVIN BRADY

The race to succeed 13-term Congressman Kevin Brady in the heavily Republican 8th District, north of Houston, has split many of the state's top Republicans between two leading candidates.

Morgan Luttrell, a former Navy SEAL, is backed by a political action committee with ties to Republican congressional leadership, as well as Lieutenant Governor Dan Patrick, former Governor Rick Perry and U.S. Representative Dan Crenshaw. Luttrell is the twin brother of Marcus Luttrell, also a Navy SEAL, who wrote the bestselling memoir "Lone Survivor."

Christian Collins, a conservative activist, is supported by the campaign arm of the House's right-wing Freedom Caucus.

REPUBLICANS GAINING GROUND

The elongated 15th District, which stretches south from the San Antonio area to the Rio Grande, is held by Democrats but was already competitive in 2020 thanks to Trump's unexpected strength among Hispanic Texans before Republicans redrew the lines in last fall's redistricting to be more favorable to them. The incumbent, Vicente Gonzalez, decided to run for reelection in the neighboring 34th District, leaving half a dozen Democrats vying for the party's nod.

The Republican front-runner is Monica De La Cruz, who narrowly lost to Gonzalez in 2020. The race could be the state's most closely contested congressional battle this fall.

DEMOCRATIC REMATCH

The Democratic primary in the South Texas 28th District will be a rematch: Jessica Cisneros, a liberal backed by Representative Alexandra Ocasio-Cortez and the left-wing Justice Democrats, will again challenge nine-term incumbent Henry Cuellar, one of the most conservative Democrats in the House, after a close 2020 contest.

An FBI raid at Cuellar's house in January has given Cisneros a boost. The agency has not commented on the matter, and Cuellar, who has not been charged with a crime, has said he is confident he will be cleared of any wrongdoing.

PROGRESSIVE PUSH

The solidly Democratic 35th District, stretching from San Antonio to Austin, will also be a test of the party's left wing. Greg Casar, a democratic socialist and former Austin city council member, is backed by high-profile liberals including U.S. Senator Elizabeth Warren and Ocasio-Cortez.

Casar faces several challengers, including state Representative Eddie Rodriguez. The incumbent, Democrat Lloyd Doggett, has opted to run in the newly created 37th District based in Austin.

BLACK REPUBLICAN VETERAN

One of two new congressional seats this year thanks to Texas' booming population, the 38th District stretches northwest from Houston and was drawn by Republicans to be safely conservative.

Wesley Hunt, a Black conservative and Army veteran who narrowly lost to Democrat Lizzie Fletcher in 2020 in a race that earned national attention, has emerged as the leading candidate for Republicans. He has been endorsed by Cruz, as well as House Republican leaders, though he faces several challengers.

(Reporting by Joseph Ax; Editing by Scott Malone and Aurora Ellis)