State Representative John Zerwas is the third Fort Bend County Republican officeholder in three weeks to announce plans to step down.

A state representative has become the third Fort Bend County Republican to announce plans to step down in as many weeks. The county's political and demographic shifts may help explain why.

State Rep. John Zerwas said Wednesday he'll resign at the end of September. Earlier in July, both Fort Bend County Sheriff Troy Nehls and Congressman Pete Olson announced they would not seek reelection in 2020.

Bob Stein, a professor of political science at Rice University, says President Trump's immigration policies hurt the GOP in the county in 2018 and could do so again in the contest to replace Zerwas.

"It's not just that there has been an emergence of Democratic voters, but it's where those voters have appeared," Stein said. "There, Asian Americans have been the big force behind the Democrats becoming a majority. Right now, between Asian Americans, African Americans and Hispanics, the majority of the registered voters in Fort Bend County are non-white."

Last year, Democrats took control of the county commissioners court and district attorney's office, as well as giving Congressman Olson his closest reelection contest ever.

"I think [Fort Bend County] Republicans feel at this point their chances of not just losing in 2020 are great, but if 2022 produces a Democratic majority in the state house, then the redistricting will make it a permanent condition," Stein said.

Under state law, Governor Greg Abbott must call a special election to fill Zerwas' seat.

MORE: What GOP Congressmen Retiring Means For Texas (Houston Matters)

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