AUSTIN, Texas (AP) — The first Hispanic female sheriff in Texas is headed to a Democratic runoff against the son of a former governor in their longshot bid to unseat Republican Gov. Greg Abbott.

Former Dallas County Sheriff Lupe Valdez and Houston investor Andrew White advanced Tuesday from a field of nine largely unknown Democratic primary candidates. The runoff election is May 22.

Texas Democrats haven't won a statewide race since 1994. The party's rising stars in Texas all passed on running for governor after Democrat Wendy Davis lost by 20 points in 2014.

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White is the son of former Texas Gov. Mark White, who served one term in the 1980s and died last year. Andrew White is a self-described "conservative Democrat" who has alienated progressives over his personal opposition to abortion.

Valdez would be the first Hispanic and openly gay governor in Texas history.