Cheney would not discuss her political plans after this month's primary. But she said she will do "whatever is necessary" to keep Trump from becoming the GOP presidential nominee for a third consecutive election in 2024.
She said she intends to be "a big part of making sure that we protect the nation" from Trump, whether she wins reelection or not.
Cheney also urged members of both parties to band against GOP candidates who have advanced Trump's lies about election fraud and are seeking to take over the election machinery of key states this fall.
Republicans in recent months have
nominated candidates who have embraced Trump's lies about election fraud for offices that control the election machinery in a series of states, including some of the nation's most competitive presidential battlegrounds: Arizona, Nevada and Pennsylvania. The party has also endorsed an election denier for the top elections post in Michigan.
"I don't think anybody should vote for any election denier," Cheney said. She cast defeating those candidates as critical to stopping Trump from circumventing the will of American voters if he is nominated for president in 2024.
"I think we have to make sure that we come together and form alliances across party lines, to make sure that the people that we are electing are not going to unravel the republic," she said.