BOSTON — Groton resident Beth Lindstrom, who has a long history within the state’s Republican Party, formally announced her candidacy for U.S. Senate Saturday, pitching herself as a newcomer to campaigning who is not afraid to take on Sen. Elizabeth Warren — or President Trump, if necessary.

Standing and speaking on a stage without a podium at District Hall in the Seaport District, Lindstrom railed against Warren and told supporters about her plans to reform the tax code and oppose so-called “sanctuary cities” for immigrants.

“I am not a professional politician. This is my first time as a candidate,” she said. “And I do not imagine for one moment that I could take up this cause alone … I am betting that if we give Massachusetts a real debate, and if we give voters a real choice, we just might give Sen. Warren a real surprise.”

Lindstrom said she’s tired of the conflict in Washington, “the nastiness of the debates and the nothingness of the results.” She suggested she would be willing to work across the aisle and oppose hyper-partisanship.

She faces an uphill battle due to a crowded and ever-growing Republican field, and Warren’s national stardom within the Democratic Party.

But Lindstrom holds a high statewide profile with her party as a longtime GOP operative. She’s a former executive director of the Massachusetts Republican Party, and then led the Massachusetts State Lottery.

She was the first woman to be executive director of the state’s Republican Party. If she wins the primary, she said, she would be the first woman in Massachusetts history to be the Republican nominee for U.S. Senate.

She also served in former Gov. Mitt Romney’s cabinet as Director of Consumer Affairs and Business Regulation.

“In all of this, I’ve learned a few things,” she said. “For example, if you really focus on the work at hand as a public official, leaving the shouting and theatrics to others, you can actually accomplish a lot.”

Lindstrom said she would be willing to work with Trump, but is not afraid to counter him when he is wrong, towing a line she said is missing in Warren and other candidates.

“Of my primary opponents, one offers blind loyalty to Donald Trump, the other blind hostility. Neither posture is very useful if we ever hope to make any progress,” she said. “As for Elizabeth Warren’s dealings with Donald Trump, let’s just say they don’t exactly bring out the best in each other.”

That was the only context in which Lindstrom directly mentioned her Republican primary challengers, a group that includes state Rep. Geoff Diehl and entrepreneur Shiva Ayyadurai.