“If you don’t have the right candidate out of the primary, that’s going to hamper your efforts in the general,” he said, in a reference to the November election.

Tarbutton’s get-out-the-vote push in Georgia is being mirrored inside companies in Kentucky, Idaho, Pennsylvania, Arkansas and Oregon, all states with congressional primaries tonight. Today’s contests are widely viewed as the pinnacle of an intraparty power struggle between groups aligned with the limited-government Tea Party and a business coalition led by the U.S. Chamber of Commerce.

The aim of the corporate coalition is to avoid the nomination of untested candidates who could hurt Republican chances of taking control of the Senate away from the Democrats in November, as happened in the 2010 and 2012 elections. Republicans need a net gain of six seats to retake the chamber.

It’s also a mission to boost candidates who are better steeped in and more supportive of the business community’s agenda, including ensuring that the nation doesn’t default on its debt.