Donald Trump will headline a fundraiser for Rep. Liz Cheney's Republican primary challenger this week, Axios has learned.

Why it matters: With competitive GOP primaries around the corner, Trump has ramped up retaliatory efforts against Republicans he considers internal enemies.

• Trump's fundraiser for Wyoming Republican Harriet Hageman is his latest effort to undercut Cheney, who voted to impeach the former president last year and is leading efforts to investigate the Capitol siege.

What's happening: The fundraiser will take place prior to a rally in Casper, Wyoming, on Saturday, according to details on the Republican fundraising platform WinRed.

• A $500 contribution gets donors access to a VIP reception. For $15,000, they can get a photo with Trump.
• The donations go to Save Wyoming, a new joint fundraising committee benefitting Hageman's campaign and Trump's Save America leadership PAC.

Between the lines: Cheney has a huge cash advantage in the nomination fight.

• She was sitting on nearly $7 million in cash at the end of the first quarter of 2022, the most recent reporting period, compared to just over $1 million for Hageman.
• Trump has tried to help close that gap with a $500,000 contribution to a super PAC backing Hageman.

The big picture: Cheney, who tops the list of Trump's intra-party antagonists, is nonetheless facing an uphill climb to the Republican nomination in August's primary.

• Her race is one of a handful the former president has focused on as a way of purging the party of its few remaining Trump critics.
• His political operation has also steered millions to efforts to unseat Georgia Gov. Brian Kemp, who's facing off against former Sen. David Purdue in a Republican primary on Tuesday.