Boosting election-denying candidates in GOP primaries could backfire and lead to grave consequences for the country, Sen. Mitt Romney (R-Utah) warned Democrats on Tuesday.

Its not illegal but it sure is stupid, Romney told HuffPost. Be careful what you wish for. You may select somebody who actually wins and then you hurt the country as well as your own party.

Romney has been a vocal critic of continued Republican efforts to cast doubt on elections with lies about fraud. He is the only GOP senator who voted to impeach former President Donald Trump over both the Jan. 6, 2021, riot on Capitol Hill and his attempt to extort Ukraine.

The Democratic Party has deployed millions of dollars in states including California, Maryland and Illinois to boost Republican primary candidates who it believes are likely to lose in the general election. Many of these candidates are right-wing figures who promote lies about the election and the Democratic strategy has come under fire from members of the party and anti-Trump Republicans who fear it could help candidates who are a direct threat to democracy.

But Democrats who have deployed the tactic believe critics are blaming them for a GOP base hungry for election denialism and other extreme positions, and drawing distinctions without real meaning between a group of Republicans openly hostile to democracy and a group that will undoubtedly acquiesce as the former acquires power. To them, deploying hard-knuckle tactics is necessary to stop the GOP.

No Republican running is willing to say Donald Trump should not be their nominee. Every Republican is flirting with the Big Lie. The crisis our country faces is not any individual Republican, but an entire party embracing and defending groups attacking democracy itself, said Marshall Cohen, the political director of the Democratic Governors Association.

Until they muster the courage to speak truth to their primary voters, they dont have a leg to stand on, he added.

Democrats have pointed to Colorado as evidence of the insincerity of GOP moderates. There, a supposed centrist candidate for governor, University of Colorado Regent Heidi Ganahl, won the primary despite Democratic efforts to boost a more conservative challenger. On Monday, Ganahl selected her running mate : A businessman who repeatedly called the 2020 election a Democrat steal and once hosted law professor John Eastman, who tried to craft legal strategies for Trump to steal the election.

The most recent Democratic meddling to boost an election denier came in Maryland, where the Democratic Governors Association has spent more than $1 million boosting the candidacy of Del. Dan Cox, a Trump loyalist and election denier running with the former presidents endorsement.

The DGAs ad, from the perspective of a general election audience in heavily Democratic Maryland, is a straightforward attack: It highlights Coxs ties to Trump, opposition to gun control and support for an abortion ban. But with Republicans having spent relatively little so far, the ad also effectively serves as a way to make GOP voters aware of Cox.

Too close to Trump, too conservative for Maryland, the ads narrator concludes.

Coxs main challenger is Kelly Schulz, who served in the cabinet of outgoing GOP Gov. Larry Hogan and has his endorsement. Hogan and Schulz have aggressively worked to make voters aware of the DGAs efforts.

Schulzs campaign has run its own video highlighting the Democratic meddling. Hes the only candidate who can ensure Democrats take back Maryland in 2022, a female narrator says of Cox. Because if you vote for crazy, Democrats win.

Polling in the race has been limited, but generally shows a competitive race with nearly half of the electorate undecided and with little impression of either candidate. Voting concludes Tuesday in the Maryland primaries.

Democrats have also sought to elevate extreme GOP candidates in Arizona, Colorado and Pennsylvania. Doug Mastriano, the Republican candidate for governor in Pennsylvania, was once seen as a long shot given his attendance on the steps of the U.S. Capitol during the Jan. 6 insurrection. Now polls show Mastriano trailing by surmountable margins to the Democratic candidate, Pennsylvania attorney general Josh Shapiro.

Former Democratic National Committee Chair Tom Perez, who is now one of the leading candidates for the Democratic nomination in Maryland, noted both parties have long meddled in the others primaries. (Famous recent and successful examples include former Sen. Claire McCaskill (D) picking her opponent in the 2012 Missouri Senate race and Democrats meddling in the 2018 West Virginia Senate race to help Sen. Joe Manchin (D) win reelection.)

Our politics has devolved, Perez said. I wish neither side would do it. But Im not a believer in unilateral disarmament.