One of the top donors for Senate Minority Leader Mitch McConnel (R-KY) has invested big money in stopping former Missouri Gov. Eric Greitens from winning the Republican Senate primary in the Show-Me State.

According to Politico, establishment Republicans have joined forces to stop Greitens and will be spending millions of dollars on advertising. The outlet reported:

The group, called Show Me Values, is set to start running TV advertisements targeting Greitens, beginning Friday. The outfit is set to air more than $1-million worth of commercials through the end of June, and a person involved with the organization said it planned to remain involved in the race up until the Aug. 2 primary.

Show Me Values is currently being funded by top Missouri Republican donors, including Rex Sinquefield and his wife, Jeanne. As Greitens pointed out on Thursday, Sinquefield has consistently supported Mitch McConnell as well as the super PAC Senate Leadership Fund.

Greitens campaign manager Dylan Johnson knocked the super PAC for being “scared” of an America First champion.

“These swamp creatures and grifters know their time at the trough is finished,” Johnson said. “That’s why they’re scared of America First champion Governor Greitens.”

Speaking with Breitbart News this past May, Greitens said that establishment Republicans fear that the base has drifted toward the “America First” movement.

What is happening is that the whole movement, the whole Republican Party is moving towards the America First movement,” Greitens said. “That’s where the people of Missouri are at. That’s where I’m at.”

Greitens further described himself as an “America first candidate running against RINOs who are supporting Mitch McConnell.”

A recent Real Clear Politics poll for the Missouri Republican primary Senate race showed that Greitens, who resigned from the governorship in 2018 over sexual assault allegations, has 24.8 percent of support from likely voters while  Missouri Attorney General Eric Schmitt trails with 21.3 percent.