Washington • Sen. Mitt Romney isn’t toeing the Republican line. He isn’t jumping on Fox News to defend President Donald Trump. He isn’t forecasting his vote to acquit or convict.

The Utah Republican has come under fire from Trump fans for his interest in hearing testimony from former national security adviser John Bolton — who may undercut the defense laid out by Trump’s lawyers — and earned hero status among those on the left who see Romney as key to bringing about a fair trial.

“I think what Romney is doing is he’s kind of holding a mirror up in people’s faces [and saying], ‘How do you want to look in this?’ ” Sen. Tim Kaine, D-Va., told The Salt Lake Tribune on Tuesday.

Democrats, who control 47 seats in the Senate, need four Republicans to join them in a vote to allow witnesses, including Bolton and possibly acting White House chief of staff Mick Mulvaney, in the Senate trial.

Senate Majority Leader Mitch McConnell told his caucus on Tuesday afternoon that he doesn’t have the votes to block witnesses even though the GOP holds 53 seats.

That doesn’t sit well with the White House or GOP leaders who had hoped to wrap up the trial this week with a vote on Friday or Saturday that is expected to acquit the president of the two articles of impeachment.

Romney is already taking heat for that.

Breitbart News, the outlet formerly run by Trump confidant Steve Bannon, tweeted its disgust with Romney on Tuesday, poking fun at a Twitter account Romney had secretly run under the pseudonym Pierre Delecto to follow family members.

“Willard Pierre Delecto cannot be distracted with things like the massive Biden Family corruption scandals and the fake ‘whistleblower’ hoax,” the news outlet tweeted. “No, Willard Pierre Delecto is laser-focused on getting President Trump.”

Trump was impeached by the House on two charges, abuse of power and obstruction of Congress, on allegations he leveraged hundreds of millions in U.S. aid and an Oval Office meeting with Ukraine’s new president, Volodymyr Zelenskiy, in exchange for the country announcing investigations into former Vice President Joe Biden and his son Hunter as well as a debunked conspiracy theory that Ukraine was behind the 2016 election interference.

Trump has denied any wrongdoing and his defense team chalks up the articles of impeachment to nothing more than Democrats wanting to overturn the 2016 election and remove Trump.

Romney, though, has shaken off any angst over the president’s earlier attack. When reminded about Trump’s profane remark about him, Romney responded last week, “That’s as accurate as it is irrelevant.”

Kaine, who was Democratic presidential nominee Hillary Clinton's running mate in the 2016 election, said Romney likely doesn't worry about the president's reactions.

“I don't think Mitt Romney needs to be afraid of anything or anybody,” Kaine said.

A former Republican member of Congress who has also faced Trump’s wrath says Romney should wear attacks by the president as a “badge of honor.”

“The fact that the president is calling Mitt Romney names means that Mitt Romney is making an impact,” said the former member, who spoke on condition of anonymity because of a contractual obligation with another news organization.

Romney, the former member said, is in a singular position to make a difference in the Senate: He's an elder statesman in the GOP who is trusted and liked and won't be up for reelection for four more years.

“If anybody can help direct this discussion it’s him,” the former member said. “He does have the ability to influence other Republicans.”

That doesn’t mean Romney won’t end up as a target of Trump or his supporters.

Sen. Kelly Loeffler, R-Ga., launched her own attack Monday, arguing Romney “wants to appease the left by calling witnesses who will slander” Trump.

Doug Heye, a former spokesman for the Republican National Committee and a CNN contributor, said Tuesday that Trump may not fear going after Romney, even if the senator is a vote the president wants for acquittal.

“To some extent, the groundwork has already been laid by some of the comments Trump has made,” Heye said. “Trump isn’t one to keep his powder dry, but voting for witnesses and voting to convict are two very separate things.”