BOSTON — Massachusetts Republican state Rep. Geoff Diehl formally launched his candidacy to unseat incumbent Democratic U.S. Sen. Elizabeth Warren Tuesday, saying she’s too focused on grabbing the spotlight while accomplishing little for the state’s voters.

Diehl, who served as co-chair of President Donald Trump’s campaign in Massachusetts, made the announcement in his hometown of Whitman.

“I think there’s an expectation in Massachusetts that senators and congressmen and women who go to D.C. should work for the people of Massachusetts,” Diehl told The Associated Press before the announcement. “What we’ve had for the past four and a half years is someone who’s had her own agenda and is raising her profile to run for president in two years.”

Warren is running for a second six-year term next year and has frequently sparred with Trump.

Diehl said he’s received the backing of former Boston Red Sox pitching great Curt Schilling, a Republican and outspoken Trump supporter who briefly toyed with the idea of challenging Warren.

Diehl said unlike Warren, he’s succeeded in helping taxpayers keep more of their money, pointing to a successful 2014 ballot question he helped spearhead that repealed a state law automatically linking future increases in the gasoline tax to inflation.

Diehl said he sides with the majority of Senate Republicans to want repeal and replace former President Barack Obama’s health care law.

He also defended Trump’s call for a ban on transgender troops serving anywhere in the U.S. military, saying Trump “was listening to the generals.”

“I think they can serve in the military but it’s not up for me to set that policy,” Diehl said. “It’s up to the military.”

Warren campaign spokeswoman Kristen Orthman said the incumbent Democrat is taking nothing for granted and is building a grassroots campaign as she continues “standing up for working families against powerful corporate interests.”

Shiva Ayyadurai, a Cambridge technology entrepreneur, also is seeking the GOP nomination.

Any Republican challenger faces a daunting task trying to unseat Warren in Massachusetts, a state where Democrats hold every seat in the state’s congressional delegation and where Democrat Hillary Clinton beat Trump by about 27 percentage points.

As of the end of June, Warren had more than $11 million in her campaign account, compared to nearly $260,000 in Diehl’s account and about $28,000 in Ayyadurai’s account, according to records filed with the Federal Election Commission.

Diehl was first elected to the Massachusetts House in 2010. In 2015, he lost a special election in the Massachusetts Senate.

Diehl was among the leaders of a proposed ballot question that would have blocked public funding for the Olympics in Boston — an effort rendered moot by the city’s withdrawal from the 2024 bidding.

Other Republicans said to be considering vying for the GOP nomination in next year’s Senate race include former Mitt Romney aide Beth Lindstrom and businessman John Kingston.