“In less than 50 days and with fewer resources than other campaigns, Ed was the architect that led our campaign to a historic victory in Iowa," Bachmann said in a statement. "I am grateful for his guidance and leadership, and fortunate to retain his valuable advice even though his health no longer permits him to oversee the day-to-day operations of the campaign."
Rollins will serve an advisory role with the campaign, while current campaign strategist Keith Nahigian assumes the role of campaign manager on an interim basis.
"Keith has played a vital role in the success we have had to date and I'm confident he can lead us to a strong finish in Iowa, New Hampshire, South Carolina and across the country," Bachmann said.
The news comes as Bachmann's standing has dropped in several polls, thanks in part to Texas Gov. Rick Perry's entrance in the 2012 GOP race.
Former Sen. Scott Brown, R-Mass., candidate for U.S. Senate in New Hampshire, holds his hand over his heart during the singing of the national anthem as he waits to take the stage for his town hall campaign rally with Sen. John McCain at the Pinkerton Academy in Derry, N.H., on Monday, Aug. 18, 2014.