By Tim Ahmann and Jason Lange
WASHINGTON (Reuters) - Former President Donald Trump endorsed Wyoming attorney Harriet Hageman's bid on Thursday to unseat U.S. Representative Liz Cheney, who was the highest-profile Republican to seek Trump's removal from office on a charge he incited the U.S. Capitol riot.
Hageman was the fifth candidate Trump has backed to challenge a Republican congressional incumbent, part of his efforts to assert dominance over the Republican Party after losing his November re-election bid to Democrat Joe Biden.
Trump's fire has been focused on the 10 Republicans in the U.S. House of Representatives who voted to impeach him on a charge of inciting insurrection in a fiery speech ahead of the deadly Jan. 6 assault on the Capitol by his supporters. He has also endorsed a challenger to Republican Senator Lisa Murkowski, one of seven in her party who voted to convict Trump on the charge. He was ultimately acquitted.
Most of Trump's post-presidency endorsements have yet to face voters in Republican nominating contests before the party seeks to win control of Congress in November 2022 elections.
He has a mixed track record with those who have already faced voters. Republican activist Susan Wright - who was seeking a vacant U.S. House seat in Texas - lost a July special election to Texas state legislator Jake Ellzey, a fellow Republican. Another Trump-backed candidate - coal lobbyist Mike Carey - won a crowded August Republican nomination contest for a U.S. House seat in Ohio.
But in Wyoming, which voted overwhelmingly for Trump last November, public opinion polls suggest Cheney's vocal criticism of the former president will hurt her chances of victory, said David Wasserman, a political analyst at Cook Political Report.
"Trump still effectively leads the Republican Party, and there's no better sign of that than in Wyoming," Wasserman said.
A Remington Research Group poll conducted in July, before Hageman's entry into the race, showed Cheney with only 19% support among Wyoming Republicans and second in a field of four candidates.
Wasserman said Cheney's best chance of winning would be if the field remains large.
Cheney, whose father Dick Cheney served as U.S. vice president from 2001 to 2009 after a previous stint in the House, is a lawmaker with impeccable conservative credentials. She is up for re-election in November 2022 to a third two-year term as Wyoming's only House member.
She responded defiantly to Trump's endorsement of Hageman. "Bring it," Cheney wrote on Twitter (NYSE:TWTR). She also said she looked forward to an "extended public debate" about the rule of law, and criticized Trump again for misleading Americans over his baseless accusations that he lost the 2020 election due to voter fraud.
Cheney has been a steady critic of Trump and earlier this month, when she was named vice chair of the congressional select committee investigating the Capitol riot, vowed she and other investigators would "not be deterred by threats."
Hageman is a well-known attorney for land rights issues, an important political issue in the U.S. West.
In a statement on the launch of her campaign, Hageman described Cheney as a politician who "betrayed us because of her personal war with President Trump."
Trump similarly called Cheney "disloyal" in a statement.