Columbia, South Carolina (CNN) - A group of loyalists to South Carolina Sen. Jim DeMint - including a top fundraiser for Rick Perry - will publicly endorse Mitt Romney's presidential bid on Thursday, a source confirmed to CNN.
Former South Carolina GOP Chairman Barry Wynn, Columbia businessman and fundraiser Peter Brown, and Columbia attorney Kevin Hall will announce their support for Romney Thursday.
Wynn's move to Romney is striking. The Spartanburg financial adviser is a member of Perry's finance team and traveled to Texas in August to meet privately with the governor before he announced his bid.
All three Republican heavyweights, who are longtime DeMint advisers, are part of an informal group of South Carolina GOP power brokers that dubbed itself the "keep your powder dry caucus" this summer to express their discontent with the current GOP field.
But their endorsement signals that Romney, the GOP frontrunner in South Carolina, has made significant inroads with the Columbia political class after his wins in Iowa and New Hampshire.
DeMint backed Romney in 2008 but has remained neutral in this presidential race.