Nearly a dozen House Republican incumbents already have credible challengers, and conservative groups expect that number to grow in the coming months as races develop and deadlines approach to qualify for the ballot. The coming fiscal battles — there’s now a Jan. 15 deadline for funding the government and a Feb. 7 deadline to raise the debt ceiling — could add fuel to the primary fires…

In the Senate, the GOP primary field is beginning to solidify, with veterans like Minority Leader Mitch McConnell of Kentucky, South Carolina Sen. Lindsey Graham and Tennessee Sen. Lamar Alexander drawing conservative opponents. And last week, state Sen. Chris McDaniel announced he will run against veteran Mississippi Sen. Thad Cochran — and the challenger swiftly won endorsements from several right-leaning groups.

“Democrats feel well represented [by their members of Congress]. But there’s a huge sense of disquiet among the base with elected Republicans,” said Daniel Horowitz, policy director for the Madison Project, a conservative group that is supporting several primary challengers to Republican incumbents, including McDaniel. “Like 2010 was the Republican wave, 2014 will be the primary wave. The threat of a primary challenge is the 800-pound gorilla in the room. … I think you’re going to see it everywhere.”