Example from Texas:

https://www.texasobserver.org/hard-right-megadonors-tim-dunn-and-farris-wilks-pump-millions-into-gop-primary-wars/

For more than a decade, the two West Texas oil and gas moguls have used their fortunes to finance an ideological crusade to oust the torchbearers of the party establishment and install champions of their far-right, theocratic agenda.

...

Dunn and Co. aren’t stopping at the statewide primaries. They’ve historically had the most electoral success by putting up big money behind challengers—and tarring GOP incumbents as liberal hacks—in state House and Senate races.

https://www.texastribune.org/2023/07/24/ken-paxton-impeachment-dunn-wilks/

Hours before the Texas House overwhelmingly voted to impeach Ken Paxton in May, a well-funded supporter of the attorney general issued a threat to his fellow Republicans.

A vote to impeach Paxton, Jonathan Stickland wrote on Twitter, “is a decision to have a primary.”

"Wait till you see my PAC budget,” he later added.

Stickland is the leader of Defend Texas Liberty, a political action committee that has donated millions of dollars to far-right candidates in the state. It is a key part of the constellation of political campaigns, institutions and dark-money groups that a trio of West Texas oil tycoons — Tim Dunn and brothers Farris and Dan Wilks— have pumped small fortunes into as part of a long-term crusade to push Texas to the extreme right.