David Bossie, who was named to lead Trump effort to challenge election results, tests positive for coronavirus

• David Bossie, who only days ago was tapped to handle President Donald Trump's effort to challenge the results of the presidential election, has tested positive for the coronavirus.
• Bossie's diagnosis was disclosed hours after news broke that Trump appointee Ben Carson, secretary of Housing and Urban Development, is positive with Covid-19, and days after White House chief of staff Mark Meadows was revealed to be positive with the virus.
• Bossie is no longer part of the decision-making process of the election challenge effort, "because he can't be at the campaign headquarters and he can't be in the Oval Office," a source told NBC News.

From left; Former U.S. Rep. John Shadegg, Citizens United President David Bossie, former Arizona Treasurer Jeff DeWitt, Arizona U.S. Rep. Debbie Lesko, R-Ariz.,speaking, Republican Party Chairwoman Kelli Ward, and U.S. Rep. Paul Gosar, R-Ariz., participate in an Arizona Republican Party news conference, Thursday, Nov. 5, 2020, in Phoenix.

Matt York | AP

David Bossie, who only days ago was tapped to handle President Donald Trump's effort to challenge the results of the presidential election, has tested positive for the coronavirus, NBC News reported Monday.

As a result, Bossie is no longer part of the decision-making process of the election challenge effort, "because he can't be at the campaign headquarters and he can't be in the Oval Office," a source told NBC News.

Bossie's diagnosis came to light hours after news broke that Trump appointee Ben Carson, secretary of Housing and Urban Development, was positive with Covid-19 and days after White House chief of staff Mark Meadows was revealed to be positive with the virus.

Two sources who spoke to NBC News said Bossie tested positive for Covid-19 on Sunday.

David Bossie, president of Citizens United, speaks during the Skybridge Alternatives (SALT) conference in Las Vegas, Nevada, on Thursday, May 9, 2019.

Joe Buglewicz | Bloomberg | Getty Images

The other source said that Bossie is believed to be at home and feeling OK.

Bossie last Thursday participated in an Arizona Republican Party press conference about the Trump campaign in Phoenix.

At that event, Bossie, who was not wearing a mask, stood alongside U.S. Reps. Paul Gosar and Debbie Lesko, both Republicans from Arizona, state party chairwoman Kelli Ward, former Trump campaign officials Jeff DeWit and Boris Epshteyn and former U.S. Rep. John Shadegg.

Lesko's spokeswoman, Rachel Harris, told NBC News that the attending physician for Congress told Lesko that she does not need to quarantine or take a Covid test.

Lesko has no symptoms of the virus, Harris said.

Trump's campaign is mounting a multistate effort to legally challenge ballots in the election contest and to recount ballots in a number of states. Bossie was appointed to head that effort on Friday, three days after Election Day.

Former Vice President Joe Biden on Saturday was projected as the winner of the election by NBC News and by other major media outlets.

Trump, a Republican who in October was diagnosed with the coronavirus, has refused to concede the election.

Bossie, who was Trump's deputy campaign manager in 2016, was put in charge of the election challenge effort by the current campaign manager, Bill Stepien, and by senior White House advisor Jared Kushner, who is Trump's son-in-law.

Bossie is head of the conservative advocacy group Citizens United.

The White House declined to comment, and the Trump campaign did not immediately respond to a request for comment on Bossie when contacted by CNBC.

— CNBC's Kevin Breuninger and Christina Wilkie contributed to this report.