Updated 12:29 p.m. | In its first endorsement of a challenger to an incumbent this cycle, the Club for Growth on Tuesday backed Republican Jim Duncan against Rep. Renee Ellmers in North Carolina’s safe Republican 2nd District.  

Although Ellmers faces at least three primary challengers, the Club concluded that Duncan, a retired businessman who chairs the Chatham County GOP, has the most viable campaign operation and the best shot at winning.  

“Jim Duncan will have to defeat Washington insider Renee Ellmers,” Club for Growth President David McIntosh said in a statement. “She campaigned as a Tea Party candidate, but sided with Nancy Pelosi in reauthorizing the corrupt Export-Import Bank, and in supporting the wasteful trillion-dollar spending bills of 2014 and 2015.”  

The Club for Growth is focused on fiscal conservatism, but Ellmers’ support for spending bills isn’t all that’s angered her socially conservative base.  

“I can’t speak for the social groups,” Club for Growth Communications Director Doug Sachtleben told Roll Call Tuesday, “but there does seem to be a larger movement on her part from the positions she took when she initially ran.”  

Ellmers campaigned as a tea party conservative, but has alienated parts of her socially conservative base since she took office in 2011.  

Earlier this year, 
Ellmers helped convince leadership to pull the GOP’s 20-week abortion ban bill
, the “Pain-Capable Unborn Child Protection Act,” and helped substitute it with a less controversial measure.  

She also sided with 75 other Republicans in passing a Homeland Security spending bill that did not address President Barack Obama’s executive order on deferred deportations.  

Ellmers earned national attention this fall when she was forced to put out a statement in response to rumors that she and House Majority Leader Kevin McCarthy were engaged in an extramarital affair after McCarthy unexpectedly dropped his bid for speaker.  

Ellmers said she was “praying for those who find it acceptable bear false witness.” Besides Duncan, Ellmers is facing primary challenges from radio talk show host Frank Roche, whom she defeated 59 percent-41 percent last cycle, and conservative Kay Daly, who has targeted Ellmers as a “RINO.”  

On Wednesday, Defending Main Street Super PAC, a group that promotes mainstream Republicans in Washington, came to Ellmers’ aide and attacked the Club for Growth.  

“Rather than save their efforts to defeat Democrats who want to raise taxes and expand government, they’re focused on internecine battles within the Republican Party,” Defending Main Street Chairman and former Ohio Rep. Steven C. LaTourette said in a release.  

“Defending Main Street Super PAC is proud to support Renee Ellmers and will again take the Club to the woodshed and insure her re-election as our party’s standard bearer in North Carolina’s Second Congressional District,” he added.  

The group backed Ellmers in 2014, too.

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