In Tuesday's Illinois Republican primary, Rep. Don Manzullo lost to Rep. Adam Kinzinger, after the two incumbent congressmen were redistricted into the same seat.

Although just a freshman, Kinzinger had the backing of the House GOP leadership, whereas Manzullo -- a 10-term veteran -- had more support from the Tea Party and conservative activists, who distrusted his opponent's close ties with the establishment.

The conservative Club for Growth does not want to see a similar situation play out in another upcoming Republican primary, so it sent a message to the GOP leadership on Wednesday to stay out.

Reps. Ben Quayle and David Schweikert will face off against each other in the Aug. 28 Republican primary for Arizona's 6th District. Club for Growth President Chris Chocola sent a letter to House GOP leaders warning them off. Otherwise, his group will jump in on the other side:

However, we note that Speaker Boehner's Leadership PAC has already made a maximum contribution to Rep. Quayle's campaign. That contribution was made before redistricting put both men in the same district, and it is our hope that it does not signal that the House leadership has decided to take sides in this primary. In the name of neutrality, we urge Speaker Boehner to contribute the same $10,000 to Rep. Schweikert that he has already given to Rep. Quayle. We also urge Leader Cantor, Whip McCarthy, and their Young Guns Action Fund to join us in staying neutral in the Arizona race.

Should it become apparent that you are choosing sides on behalf of Rep. Quayle, the Club for Growth PAC will consider it necessary to intervene on behalf of Rep. Schweikert. As is our practice, if the Club's PAC entered this primary, it is highly likely that our 75,000 members would donate considerably more funds to Rep. Schweikert's campaign than the Republican House leadership would contribute to Rep. Quayle's campaign.

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