Former Rep. Liz Cheney of Wyoming, a one-time rising Republican Party star who became a top GOP critic of former President Trump, says she'll vote for Democratic nominee Vice President Kamala Harris in the 2024 election.

"I don’t believe we have the luxury of writing in candidates’ names, particularly in swing states," Cheney said Wednesday at a speaking event at Duke University in North Carolina.

And she emphasized that "as a conservative, as someone who believes in and cares about the Constitution, I have thought deeply about this, and because of the danger that Donald Trump poses, not only am I not voting for Donald Trump, but I will be voting for Kamala Harris."

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Kamala Harris at rally

Vice President Kamala Harris speaks during a campaign event in Detroit, Michigan, US, on Monday, Sept. 2, 2024. (Emily Elconin/Bloomberg via Getty Images)

Minutes after the Cheney news broke, the Trump campaign posted on social media an interview of Cheney on the Fox News Channel from four years ago taking aim at Harris.

"Her voting record in the Senate is to the left of Bernie Sanders and Elizabeth Warren," Cheney argued at the time. "It's very clear, she is a radical liberal."

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The Fox News interview took place soon after then-2020 Democratic presidential nominee Biden named then-Sen. Harris as his running mate.

Cheney, the daughter of former Vice President Dick Cheney, was once a conservative star in the GOP who was rising in the ranks of House Republican leadership.

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But she was the most high-profile of the 10 House Republicans who voted to impeach then-president Trump in early 2021 on a charge of inciting the deadly attack Jan. 6 on the Capitol, which was waged by right-wing extremists and other Trump supporters who aimed to disrupt congressional certification of Biden’s Electoral College victory in the 2020 election.

Liz Cheney

Former Rep. Liz Cheney of Wyoming attends a speaking engagement on June 26, 2023, in New York City.  (Gary Gershoff/Getty Images)

The conservative lawmaker and defense hawk immediately came under verbal attack from Trump and his allies, and was eventually ousted from her number-three House GOP leadership position.

Cheney, who has been vocal in emphasizing the importance of defending the nation's democratic process and of putting country before party, was one of only two Republicans who served on a special select committee organized by House Democrats that investigated the riot at the Capitol.

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In 2022, she was ousted in the GOP congressional primary in Wyoming to a candidate that was backed by Trump.

Cheney — who has argued that the former president is a "liar," a "con man" and a potential "tyrant" who, if elected again, would "torch the Constitution" — vowed after leaving Congress that "I will do everything I can to make sure [Trump] is never anywhere near the Oval Office again."

Trump at a campaign rally

Republican presidential nominee former President Donald Trump speaks during a rally at 1st Summit Arena at the Cambria County War Memorial, in Johnstown, Pa., Friday, Aug. 30, 2024.  (AP Photo/Rebecca Droke)

But despite outreach from the Biden campaign, which transformed into the Harris campaign in July after the vice president replaced her boss at the top of the Democrats' 2024 ticket, Cheney had remained silent until now.

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Cheney decided against joining other high-profile anti-Trump Republicans — such as former Rep. Adam Kinzinger of Illinois and former Georgia Lt. Gov. Geoff Duncan, who had speaking roles at last month's Democratic National Convention in support of Harris.

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