(CNN) – Michele Bachmann campaign manager Ed Rollins is stepping into an advisory role and deputy manager David Polyansky is leaving the campaign, Rollins said Monday.
Rollins, who’s 68 and had a stroke a year and a half ago, cited health reasons for his decision.
"I just don't have the endurance to go 12 to 14 hours a day, seven days a week anymore," Rollins told CNN's Anderson Cooper on Monday.
Rollins said he still has great affection for Bachmann and pledged to give her counsel moving forward.
"At the end of the day, I'm not going away," Rollins said.
Rollins has been with the campaign since early June. The hire was a big get for Bachmann, as Rollins helped former Arkansas Gov. Mike Huckabee spearhead a campaign that eventually won the Iowa caucuses in 2008.
"Ed is moving away from the demanding day-to-day operations of the campaign and into a serious advisor role," press secretary Alice Stewart said in a statement. "He is fantastic and will continue to be invaluable on the campaign."
Late Monday night, Bachmann's team announced Keith Nahigian, current campaign strategist, as the new interim campaign manager.
"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 in a statement.
Politico first reported deputy campaign manager Polyansky’s departure earlier Monday, saying he had "strategic differences" with Bachmann.
When asked about the conflict, Rollins told CNN that there are always differences in a campaign.
"David did a superb job. He ran the straw poll in Iowa," Rollins said. "I think David just decided–because we worked so well together–that he was going out, too."
However, Rollins said Texas Gov. Rick Perry's recent entrance into the race has made a difference in Bachmann's campaign.
"Legitimately, it's a Romney-Perry race," Rollins said. "I think she's the third candidate at this point in time, which is way different and better than we thought when we started this thing. She's very much in this thing."
He said Bachmann's key role in the next couple of weeks will be her performances in the debates.
- CNN's Steve Brusk and Peter Hamby contributed to this report.
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