Tea Party activists and supporters of Ron Paul are expected to back GOP presidential nominee Mitt Romney, but they'd like one thing from him first: Romney's endorsement of the former candidate's call to audit the Federal Reserve.

Romney recently sent out a tweet complimenting Paul's "Audit the Fed" campaign, an indication he might adopt Paul's call.

Paul's supporters and Tea Party activists could bolster Romney's campaign, and the candidate has been under pressure to do more to woo them. But a key Paul insider said that the former candidate's base will likely get behind Romney, especially if he adopts the anti-Fed effort. "That will bring along a good chunk of the Tea Party," said the source.