The move came after congresswoman Liz Cheney of Wyoming was stripped of her House Republican leadership position over her criticism of Mr Trump’s fraudulent claims that the 2020 election was stolen from him.
Mr McMullin ran for president as an independent in 2016, and Mr Taylor is a former Homeland Security chief of staff in the Trump administration who wrote the “anonymous” op-ed in The New York Times.
George Conway, the husband of former White House counselor Kellyanne Conway, is part of the group, which he says is not a third political party but a movement.
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Other Republicans who have signed on include former Massachusetts governor Bill Weld and former South Carolina governor Mark Sanford.
It also includes 27 former members of the US House of Representatives, including Barbara Comstock, Charlie Dent and Paul Mitchell, as well as former senator David Durenberger.
Other members include former White House communications director Anthony Scaramucci, former Department of Homeland Security official Elizabeth Neumann, and former DHS general counsel John Mitnick.
Mr Trump took to his recently launched blog to attack Mr Taylor and the new group.
“He is a phony who will probably be sued over his fake book and fake ‘Anonymous’ editorial, which caused so much treasonous stir,” wrote Mr Trump.
“Miles Taylor and his fellow RINO losers like Tom Ridge, Christine Todd Whitman, and Crazy Barbara Comstock voted for Biden, and now look what they have — a socialist regime with collapsing borders, massive tax and regulation hikes, unrest in the Middle East, and long gas lines.
“He is even giving us men setting new records playing women’s sports. What a disaster for our Country (sic) it has been!”
Mr Trump set up a blog after being banned from most social media platforms in the wake of the 6 January attack on the US Capitol by his supporters.
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