For those in the Republican party who support Donald Trump, Liz Cheney has been a major thorn in their side.

Rep. Liz Cheney (R-WY) has sunk 30 points behind Donald Trump-endorsed Harriet Hageman in the Wyoming GOP primary, a Club for Growth poll found Saturday.

Hageman garnered 56 percent support, while Cheney only earned 26 percent, a 30 percent difference.

The poll was conducted with 400 likely Republican primary voters in Wyoming from May 24-25. The margin of error is +4.9 percent.

A January straw poll revealed Hageman held a commanding lead over Cheney. The poll, conducted by the Wyoming Republican State Central Committee via secret ballot, showed Hageman won 59 votes and Cheney six, a 53-point victory by Hageman.

The new polling data comes after Donald Trump announced he would hold a rally for Hageman on Saturday at 4 p.m. in Casper, Wyoming. Trump and Hageman will be joined at the rally by Reps. Andy Biggs (R-AZ), Matt Gaetz (R-FL), and Lauren Boebert (R-CO). House Minority Leader Kevin McCarthy (R-CA) and Reps. Elise Stefanik (R-NY) and Jim Jordan (R-OH) will also make video appearances.

Trump’s appearance in Wyoming is likely to give Hageman an extra booster against Cheney, who has allied herself with House Speaker Nancy Pelosi’s (D-CA) January 6 committee.

Cheney has also benefited from a Democrat-linked public relations firm encouraging Democrats to vote in the open Republican primary. The public relations firm has worked for President Joe Biden’s campaign arm, Planned Parenthood, and Black Lives Matter in the past.

Cheney’s actions caused the Republican caucus to oust Cheney with a vote of no confidence in May of 2021. In November, the Wyoming GOP voted to no longer recognize Cheney as a Republican, though Cheney has continued to call herself one.

In February, McCarthy endorsed Hageman over Cheney, a rare move for a House minority leader. Hageman also has the support of MAGA billionaire donor Peter Thiel.