ROCHESTER — Minnesota Gov. Mark Dayton has undergone spinal surgery that will likely sideline him at least through New Year’s.

Dayton spokeswoman Kathleen Tinucci said the Mayo Clinic surgeon who performed the procedure Thursday reports it went as planned, without any complications. She said the governor was out of surgery and awake by mid-afternoon.

Dayton hopes the operation will relieve a constriction in his lower back, known as stenosis, which Mayo said is generally caused by normal wear-and-tear on the spine due to aging. The procedure involves fusing vertebrae that shift out of alignment.

Dayton turns 66 in a few weeks.

He is scheduled to be released by Monday and will then return to St. Paul. He plans to work from the Governor’s Residence during his recuperation period.