Trump, on the other hand, has despised Cheney ever since she voted to impeach him in 2021. This intensified after she co-chaired the House committee that investigated the January 6 attack - the committee blamed him for the deadly riot and recommended charges against him.
Months later, Special Counsel Jack Smith indicted Trump for trying to overturn his 2020 election defeat, outlining the scale of his actions in a new court filing made public this week.
Exiled by much of her party, Cheney ended up losing her seat in Congress to a Trump-endorsed candidate, but until she came out in support of Harris last month, it was widely believed she would not go so far as to back a Democrat.
It was not an easy decision, Cheney explained at the time, “but those of us who believe in the defence of our democracy, in the defence of our Constitution, and the survival of our republic have a duty in this election cycle to come together to put those things above politics”.
Equally unfathomable was the idea that her father, who served as vice president to George W. Bush and has been reviled by Democrats for his role in the 2003 US invasion of Iraq – would also back Harris.
However, he did so last month, warning that Trump had sought to “steal an election” and “can never be trusted with power again”.
“In our nation’s 248-year history, there has never been an individual who is a greater threat to our republic than Donald Trump,” he said in a statement.
The Cheneys’ endorsement is designed to show the breadth of Harris’ support and entice people who may be Republican-leaning but do not like Trump or his brand of politics.
Standing on stage next to Cheney, Harris said that anyone seeking the presidency should value free and fair elections. She added: “If you share that view, no matter your political party, there is a place for you with us.”
Since becoming the Democratic nominee, the US vice president has built a broad coalition, ranging from progressive stalwarts such as Bernie Sanders, to Taylor Swift fans and Republicans such as former Georgia lieutenant governor Geoff Duncan, former Arizona senator Jeff Flake and former White House staffer Stephanie Grisham.
However, not all Democrats agree with the strategy to side with Republicans.
“Republicans are not gonna save us, and touting their endorsements is turning people off,” said Georgia state representative Ruwa Romman, the first Muslim woman elected to the legislature there.
Trump, meanwhile, spent the day campaigning in the Midwest state of Michigan which, along with Wisconsin and Pennsylvania, are viewed as states either candidate must win for a clear path to the White House.
He opened his rally by taking aim at Harris’ running mate, Tim Walz, over his debate performance against J.D. Vance this week, before accusing Harris of destroying the country as part of the Biden-Harris administration.
“Jimmy Carter was a brilliant president compared to Joe Biden and Kamala Hamala,” Trump said, once again deliberately botching her name.
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