WASHINGTON (AP) — The House's only black Republican has become the latest GOP lawmaker to say he won't seek reelection next year, jolting the party's efforts to appeal to minority voters and wounding its already uphill chances of regaining House control.

Rep. Will Hurd, a moderate Texan who's clashed with President Donald Trump over race and immigration, used an evening tweet to announce he would not seek re-election next year. That made him the ninth House Republican to say they will depart — the sixth in just over a week — and gives Democrats a strong shot to capture a district that borders Mexico and has a majority Hispanic population.

Hurd's exit put the GOP ahead of its pace when 34 of its members stepped aside before the last elections — the party's biggest total since at least 1930. It also underscored how Republicans are struggling to cope with life as the House minority party, today's razor-sharp partisanship and Trump's tantrums and tweets.

Republicans say they don't expect this election's retirements to reach last year's levels.

But their more ominous problem is embodied by Hurd, one of several junior lawmakers to abruptly abandon vulnerable seats and a visible symbol of the GOP's attempt to shed its image as a bastion for white males.

The recent spate of departures puts perhaps four GOP seats in play for 2020 and suggests an underlying unease within the party about the hard realities of remaining in Congress.

"There's a mood of tremendous frustration with the lack of accomplishment," Rep. Paul Mitchell, R-Mich., said in an interview this week, days after stunning colleagues when he said he's leaving after just two House terms. "Why run around like a crazy man when the best you can hope is maybe you'll see some change at the margins?"

Mitchell, 62, who said he originally intended to serve longer, blamed leaders of both parties for using the nation's problems "as a means to message for elections" instead of solving them.

He also expressed frustration with Trump's tweets last month telling four Democratic congresswomen of color — including his Michigan colleague, Rep. Rashida Tlaib — to "go back" to their home countries, though all are American. The tweet was "below the behavior of leadership that will lead this country to a better place," Mitchell said.

In a statement, Hurd did not mention Trump but pointedly said he'd held onto his seat "when the political environment was overwhelmingly against my party." The former CIA operative said he was pursuing opportunities in technology and national security.

Hurd, 41, was a leader in a failed bipartisan effort last year, opposed by Trump, to help young immigrants brought to the U.S. illegally stay in this country. He was also among just four Republicans to last month back a Democratic condemnation of Trump's "go back" insult as racist.

Just a day earlier, Rep. Michael Conaway, R-Texas, also said he won't seek reelection, which he attributed to his loss of a leadership role atop his beloved House Agriculture Committee. Conaway, 71, represents a central Texas district that is safe Republican territory.

Republicans say it can be demoralizing to be in the minority in the House, where the chamber's rules give the majority party almost unfettered control. That leaves them with little ability to accomplish much, even as they must continue the constant fundraising that consumes many lawmakers' hours.

"When you've been in the majority, it's no fun to be in the minority," said veteran Rep. Tom Cole, R-Okla.

But other Republicans in the Capitol and outside it — several speaking on condition of anonymity to avoid alienating colleagues — say the frustration runs deeper. They describe worries that they won't win back the majority in 2020, which would mean two more years of legislative futility, and exasperation over Trump's outbursts, including his racist tweets taunting the four Democratic women.

"The White House isn't helping the atmosphere up to this point for these guys. They're having to answer every day for things they didn't say or do," said former Rep. Tom Davis, R-Va. "That's not a good place to be."

Michael McAdams, a spokesman for the National Republican Congressional Committee, said the retirements are "what happens this time of year." He said Republicans are "in a prime position to pick up seats and recapture the majority."

In another blow to the GOP's reach for diversity, it is losing two of the mere 13 House Republicans who are women. Rep. Martha Roby of Alabama , 43, like Michigan's Mitchell, is vacating a deeply red seat, while the retirement of Susan Brooks, 58, could put her Indiana seat at risk.

Reps. Rob Woodall of Georgia, 49, and Pete Olson of Texas, 56, would have faced difficult races had they run for reelection. Their departures are unhelpful for a party that must gain at least 18 seats to win the majority.

In next year's House contest, history favors Democrats, who have a 235-197 majority with two vacancies and one independent.

The last time a president ran for reelection and any party gained at least 18 House seats — the minimum Republicans need to take over — was 1964, when President Lyndon Johnson's landslide netted Democrats a 37-seat pickup.

Party control of the chamber hasn't changed during a presidential election since 1952, when Republican Dwight Eisenhower won the White House and majority Democrats lost the House.

On the practical side, the House's 62 freshmen Democrats and the party's other vulnerable lawmakers have energetically raised money for their reelection campaigns. Even first-termers in GOP-friendly districts in Oklahoma City, Salt Lake City and Charleston, South Carolina, have banked significant early funds.

The GOP's rules for seniority are also a factor. Texas' Conaway and fellow retiree Rep. Rob Bishop, R-Utah, will both exhaust the self-imposed six-year limit the House GOP allows for lawmakers to chair a committee or serve as its top Republican. Bishop, 68, will be ending his run atop the Natural Resources Committee.

Another retiring Republican, Alabama Rep. Bradley Byrne, 64, is running for Senate and leaves behind a solid Republican district.