The presidential campaign of Montana Gov. Steve Bullock is fundraising off claims that Republican forces fear his candidacy — even though the attacks are to damage him in a Senate run if, as expected, he drops out of the White House race.

Bullock's campaign suggested his candidacy intimidates the Koch brothers so much that they launched attack ads against him. But the “Koch Brothers smear campaign” in question has little to do with Bullock’s candidacy for president.

Another email sent to supporters last week brought attention to “Republican SuperPAC ATTACKS.” But those are targeted at a potential Bullock Senate bid, according to a source knowledgeable about the effort.

“The Koch Brothers just launched one of their first attack ads of the Presidential campaign ... and their target is STEVE BULLOCK,” a fundraising email sent to supporters Tuesday night read. “Governor Bullock has fought against the Koch Brothers before — and he’s won. So now, they’re trying to stop the incredible momentum of his campaign.”

Bullock's support is currently at 0.4% support in the RealClearPolitics average of primary polls.

Throughout his campaign, Bullock has touted Montana’s strict campaign finance laws and taken aim at billionaires Charles Koch and David Koch, who back a network of libertarian and conservative political and policy organizations. The Kochs often support Republicans, but they reportedly plan to stay out of the 2020 presidential race and instead focus on down-ballot contests. David Koch retired from all business and advocacy work last June due to health.

The Bullock campaign pointed the Washington Examiner to a form letter campaign from Americans for Prosperity, the main Koch network advocacy group, asking Montana officials to override Bullock’s veto of a bill intended to protect free speech on public college campuses.

Americans for Prosperity-Montana in recent weeks placed digital radio, traditional radio, and Facebook ads in the state urging residents to sign the form letter. None of the ads mention Bullock's candidacy for president.

“Our universities can lead the way in promoting an open exchange of ideas, and this bipartisan legislation would have helped to ensure that. But it’s not too late! Our representatives can still vote to override the governor’s veto,” the digital radio ad says.

The ads were a continuation of an effort that started before Bullock announced his candidacy on May 14, an Americans for Prosperity spokesperson told the Washington Examiner. In April, the American Civil Liberties Union of Montana worked with Americans for Prosperity to advocate for the campus free speech bill.

Americans for Prosperity-Montana "and a broad coalition of groups have long encouraged state lawmakers to protect free expression for students and faculty on Montana’s public college campuses,” the spokesperson said. The group has supported similar campus free speech bills in other states, including Iowa, South Dakota, and Oklahoma.

In a May 7 letter explaining his veto, Bullock argued the bill provided a “weak remedy” to protect free speech and free expression and that current university policies in the state adequately protect those rights.

The Bullock campaign did not respond to requests for comment about its characterization of the Americans for Prosperity campaign.

The Senate Leadership Fund, a super PAC founded by allies of Senate Majority Leader Mitch McConnell, on May 29 announced an eight-day, $150,000 television and digital ad campaign in Montana markets against Bullock. The ads accuse Bullock of taking "advantage of Montana tax dollars for political gain" and "running for president on Montana's dime," noting that Montana Highway Patrol accompanies Bullock on out-of-state campaign trips.

“They know that Governor Bullock is our best chance to win back the White House!!” the Bullock fundraising email said.

Though the ads are technically classified as expenditures against Bullock’s presidential candidacy, a Senate Leadership Fund source told the Washington Examiner that the ad campaign is intended to damage Bullock’s reputation in Montana in case he decides to abandon his presidential bit and launch a 2020 Senate campaign challenging Sen. Steve Daines, R-Mont. That is why the ads are only in Montana and not in early primary or caucus states such as Iowa or New Hampshire, the source said.

Bullock is in danger of missing the Democratic National Committee’s threshold to qualify for the first round of presidential primary debates later this month: campaign donations from 65,000 people or 1% support in three approved polls. The DNC is not considering a Washington Post/ABC poll that would have pushed Bullock over the mark, and he has not announced that he has met the fundraising goal. The deadline to qualify is next Wednesday.

The Bullock campaign did not respond to a request for comment.