Republican state Sen. Mimi Walters has a 94 percent lifetime rating with California’s anti-tax group, but that might not be enough for her to avoid a anti-tax primary challenger as she runs for Congress.

Walters is the early front-runner to replace retiring Rep. John Campbell (click here for Roll Call’s interview with her). And by every traditional measure, she should win the seat easily. But one vote for a Democrat-sponsored tax extension (SB 11) is being viewed as ideological treason by some anti-tax conservatives.

Howard Jarvis Taxpayers Association
Americans for Tax Reform

It remains to be seen whether they will be successful. But the fact that Walters isn’t conservative enough for some Republicans is a great example of the civil war within today’s GOP.

California’s 45th District is rated Safe Republican by Rothenberg Political Report/Roll Call.