Republican presidential candidate Ben Carson's campaign took another hit Monday after the New Hampshire staff of his allied super PAC resigned, indicating that they are putting their support behind Texas. Sen. Ted Cruz.

The departure of five staffers in the New Hampshire branch of the "2016 Committee" super PAC — nearly the entire staff — is the latest sign that Carson's campaign is losing steam after months of declining support in national polls. The resignations were first reported by local ABC affiliate WMUR

“We hold Dr. Carson in the highest regard,” Jerry Sickles, the former spokesman for the super PAC's New Hampshire staff, told WMUR. “This is a man we revere, but we think it is important that our party nominate a conservative and get behind a single conservative who can win, and we strongly believe that candidate is Ted Cruz.”

With three weeks to go before the Feb. 1 Iowa caucuses, political observers have all but counted out the retired neurosurgeon, whose waning support was further emphasized following the year-end resignations of campaign manager Barry Bennett and communications director Doug Watts. The two left the campaign during an increasingly public feud with Carson's longtime business manager, Armstrong Williams.

Carson has sought to correct course, naming Robert Dees, a retired Army major general, as his campaign chairman and Ed Brookover as the new campaign manager. On Monday, Carson also announced that Larry Ross, a public relations strategist who has worked with countless high profile Christian leaders, will serve as communications director.

The campaign is now intent on re-energizing the grass-roots support of social conservatives in Iowa, aiming to finish within the top tier of candidates in Iowa to build momentum moving into other primary contests. Hundreds of supporters gathered to hear Carson speak last week during a packed campaign swing through Iowa. But while many of the social conservatives in attendance said they still deeply admire Carson, many also said they are nonetheless considering voting for other candidates — and in particular Cruz.

Carson faces a steeper challenge in New Hampshire, where critics say he has not campaigned aggressively enough and where polls show him trailing nearly every other Republican candidate.

The campaign indicated Monday that it is optimistic that Carson will have a strong showing on caucus day in Iowa.

"As the two are separate, we don't know why they left, but the campaign is excited about the support we have on the ground and the revitalized energy of the campaign in general," said new campaign spokesperson Jason Osborne. "We are looking forward to the next few weeks and are confident that our support will continue to grow."

Osborne added that the New Hampshire campaign is "going strong," with 10 staff members and "hundreds of volunteers."