Attorney William Johnson, a leader of the American Freedom Party and self-proclaimed white nationalist, pauses for photos in his office, Tuesday, May 10, 2016, in Los Angeles. Donald Trump's campaign says a computer problem resulted in the prominent white nationalist being included on a list of his potential California delegates. The campaign says the name has been withdrawn and a corrected list resubmitted to state officials. (AP Photo/Jae C. Hong)

William Johnson, white supremacist for Trump.

Photo: Jae C. Hong/AP

Apparently concerned about the real possibility that Donald Trump could lose the state of Utah to a third-party candidate, Evan McMullin, a political action committee run by a white supremacist backing Trump plans to target Mormon voters there with homophobic voice-mail messages.

The recorded message, urging voters to support Trump, features the voice of William Johnson, a Los Angeles lawyer and self-described “white nationalist” who narrowly missed out on being a Trump delegate at the Republican National Convention this summer.

The complete audio, obtained and posted on Soundcloud by Talking Points Memo, mocks McMullin’s mother for being “a lesbian married to another woman,” and goes on to suggest, without evidence, that the former intelligence agent and congressional staffer is himself “a closet homosexual.”

McMullin, who told the Salt Lake Tribune last week that he supports his mother even though he disagrees with her about same-sex marriage, posted a link to a Daily Beast report on the robocall on Twitter, calling the effort a “desperate attack.”

The ad was paid for by Johnson’s American National Super PAC. In an interview with the Daily Beast, Johnson defended the innuendo in the recording, claiming that it was supported by rumors on Reddit.

McMullin, who is supported by anti-Trump Republicans in Utah repulsed by the party’s nominee, continued to attack Trump for the ad, even though there was no sign of coordination with the campaign.

In an interview with CNN earlier this month, McMullin said Trump “has certainly empowered the white nationalist/ white supremacist movement, absolutely, and he’s brought them in to the Republican base.”

During the Republican primary campaign, Johnson recorded a similar call in support of Trump urging voters in Vermont and Minnesota to fight the “gradual genocide against the white race,” by rejecting Ted Cruz and Marco Rudio. “Don’t vote for a Cuban,” the call said. “Vote for Donald Trump.”