From the left; Former US Representative John Shadegg, President of Citizens United, David Bossie, Former Arizona Treasurer Jeff DeWitt, US Representative for Arizona, Debbie Lesko, R-Ariz. Attend a Republican Party of Arizona press conference in Phoenix on Thursday, November 5, 2020.
Matt York | AP
David Bossie, who was tapped just a few days ago to tackle President Donald Trump's efforts to question the presidential election results, tested positive for the coronavirus on Monday, according to Cor News.
As a result, Bossie is no longer part of the campaign process decision-making process "because he cannot be at campaign headquarters or the Oval Office," a source told NBC News.
Bossie's diagnosis leaked hours after news that Trump Housing and Urban Development Secretary Ben Carson was positive about Covid-19 and days after White House Chief of Staff Mark Meadows was found to be positive about the virus.
Two sources speaking 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 Bossie is probably home and feeling fine.
Bossie attended a Republican Party of Arizona press conference on the Trump campaign in Phoenix last Thursday.
At this event, Bossie, who was not wearing a mask, stood next to US Representatives Paul Gosar and Debbie Lesko, both Republicans from Arizona, State Party chairman Kelli Ward, former Trump campaign officer Jeff DeWit and Boris Epshteyn, the former US representative John Shadegg.
Lesko spokeswoman Rachel Harris, spokeswoman for Congresswoman Debbie Lesko, told NBC News that Congressional doctor Lesko said she did not need to do a quarantine or Covid test.
Lesko has no symptoms of the virus, Harris said.
Trump's campaign is seeking multiple states to legally challenge the ballot papers in the campaign and to reiterate the ballot papers in a number of states. Bossie was appointed to lead this effort on Friday, three days after election day.
Former Vice President Joe Biden was forecast to be the election winner on Saturday by NBC News and other major media outlets.
Trump, a Republican self-diagnosed with coronavirus in October, has refused to allow the election.
Bossie, who was Trump's 2016 deputy campaign manager, has been blamed for campaign efforts by current campaign manager Bill Stepien and senior White House adviser, Jared Kushner, who is also Trump's son-in-law.
Bossie is the 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.
– Additional reporting from Kevin Breuninger and Christina Wilkie