Republican challenger Geoff Diehl has argued in his Senate campaign that he will be a more effective force in Washington than Democratic incumbent Elizabeth Warren, reminding Massachusetts voters that her seat was once held by Edward M. Kennedy, who worked with presidents and governors of the opposite party to deliver for the state.

“That’s the record I want to have,’’ Diehl said in the most recent debate, echoing comments he has made on the stump.

But during Diehl’s nearly eight years in the Legislature, he did not engage in many bipartisan initiatives, according to a Globe review of his legislative portfolio and interviews with those on and around Beacon Hill. Since the Whitman Republican’s election in 2010 over a Democratic incumbent, Diehl has been a leading member of a small band of conservative dissidents — a lawmaker who readily bucks his own party as well as Democratic leadership.

Only two bills of which Diehl was the primary cosponsor — both during his first term in the overwhelmingly Democratic Massachusetts House — have become law. One dealt with tax titles in East Bridgewater, the other amended the town charter of Abington.

The policy accomplishment that Diehl most frequently touts in debates and his lone television ad involved winning a voter repeal of Democratic-backed legislation passed in 2013. Diehl helped lead a successful ballot initiative the next year that repealed automatic increases to the state’s gas tax indexed to inflation.

The effort, which involved an army of volunteers who collected more than 140,000 signatures, has saved taxpayers $2 billion, Diehl says.

“I’ve basically worked with people on Beacon Hill, or sometimes — like with the gas tax ballot question — outside of the Legislature to try to enact what I think is important legislation or changes to policy that are going to benefit the people who elected me,’’ he said in an interview. “That’s my modus operandi.’’

He pointed to a letter he authored with Representative Josh Cutler, a Democrat whose district shares a regional school with Diehl’s, that Diehl says helped secure additional funding for the school. (Cutler did not respond to a request for comment). Diehl also recalled his partnership with Evan Falchuk, a one-time United Independent Party gubernatorial candidate, now a Democrat, to propose a ballot initiative to block the use of taxpayer money for the Olympics in Boston.

On Beacon Hill, his own party leadership removed Diehl from the powerful House Ways and Means Committee in 2015. The reason House minority leader Bradley Jones gave at the time: Diehl was too hard to work with.

“Others have demonstrated a better ability to work with the Republican leadership office,’’ Jones told the Boston Herald at the time. Jones declined to comment for this story.

Diehl is one of the Legislature’s most conservative members, so it follows that he doesn’t see eye-to-eye with many of his colleagues on certain policy issues.

Diehl was one of seven Republicans in July to vote against a bill that eliminated archaic state law banning abortion, and voted against the passage of a bill banning the discrimination against transgender people in 2016, which passed the House 117-36. This past session, he was a lead sponsor on a failed bill that would have allowed residents to indicate on their income tax return that they did not want their taxes to be used “to pay for abortion services.’’

In June, Diehl — who has been endorsed by the Gun Owners’ Action League, the Massachusetts National Rifle Association affiliate — voted against compromise legislation, known as “red flag’’ legislation, that gives courts the authority to strip weapons from people who have been identified by their families as a danger to themselves or others.

His allies describe Diehl as a hard-working, decent colleague who has had to work with Democrats to deliver on local initiatives and spending priorities, given their sizable majority in the Legislature.

“I know Geoff to be a very thoughtful person that will work on an issue with whoever wants to work on it,’’ said Shaunna O’Connell of Taunton, who sits next to Diehl in the chamber. “He’s also someone that isn’t going to sit down and just go along to get along and I think those are good qualities in a person, especially in politics.’’

More recently, Diehl has pointed to his passing legislation “holding lawmakers personally accountable for sexual harassment lawsuits,’’ as a campaign robocall put it. It’s a reference to an amendment Diehl successfully attached to new internal House rules for dealing with workplace sexual harassment.

Marjorie Decker, the Democratic state Representative in charge of the measure on the floor, called it “disingenuous’’ for Diehl to claim credit for any accomplishments on sexual harassment. She managed the debate on the floor and worked with people on the package, and “he certainly never reached out to me as a person who was engaged in carrying this through on the floor.’’

“He’s not a go-to person in any kind of bipartisan capacity. He doesn’t work well with members of his own party,’’ said Peter N. Ubertaccio, a professor of political science at Stonehill College.

Ubertaccio said Diehl has a more credible argument when he tells voters he will have a better working relationship with the Trump administration than Warren ever will.

In May, he was one of just four House members — all Republicans — to vote against a bill, which later become law, instituting a $2 fee on car rental transactions across the state to put up to $10 million annually toward training for local police.

Diehl, who has fashioned himself as the race’s law-and-order candidate and has picked up more than a dozen law enforcement association endorsements, explained his vote as one of standing on principle. The legislation, he said, levied what he considered an unnecessary fee when there was enough revenue in the state coffers without it.

Beacon Hill lawmakers gave themselves $18 million in pay raises at the start of the session, “yet they told police the only way we’re going to be able to train you is to raise a tax. That was pretty insulting in my opinion, and just sent the wrong message,’’ he said.

Diehl’s “no’’ vote left some in the law enforcement community cold. “We are well aware who voted for this historic legislation to enhance police training in our state for which we owe a debt of gratitude and who did not — despite their suggested rationale for their respective no votes,’’ Chelsea Police Chief Brian Kyes, president of the Massachusetts Major City Chiefs of Police Association, told the Globe.

The Massachusetts Police Association, the state’s largest law enforcement union, was unfazed, with members voting at their annual meeting Thursday in Plymouth to endorse Diehl with a thunderous “aye’’ and two standing ovations.

Diehl said his focus has always been making sure he delivered on his promises to the people who elected him: holding government accountable, letting them keep more tax dollars in their pockets, and getting what they paid for from state government.

“I’m not up there to make friends. I’m there to do the job I was elected for,’’ he said.

Globe correspondent Matt Stout contributed to this story. McGrane can be reached at victoria.mcgrane@globe.com. Follow her on Twitter @vgmac.