Lt. Gov. Andre Bauer, a fellow Republican, told The Associated Press that he spoke to Sanford on Thursday and "could tell he had done a lot of soul searching." The two, who have not been allies and don't run on the same ticket, didn't discuss the possibility of the governor stepping down.
"Mark Sanford is still my governor and regardless of what his decision is, I'm going to stand by and try to help him," Bauer told AP in his first interview since Sanford admitted to the affair Wednesday.
While others have called for Sanford's resignation, the governor planned a meeting of state agency heads Friday.
Sanford disappeared to Buenos Aires last week, returning Wednesday to reveal the affair and publicly apologize to his wife and four sons, his supporters and constituents. He also resigned as chairman of the Republican Governors Association.
Sanford said he left his staff with the impression he was heading off for some solo hiking on the Appalachian Trail, a bogus story that they relayed to reporters who began asking where the governor had gone.
He didn't tell the lieutenant governor where he was, and Bauer said he was rebuffed by Sanford's staff when he tried to find out. Sanford faces questions about whether he broke the law when he disappeared without transferring power.
The governor has not addressed the legal questions, but Sanford on Thursday said he would pay back an undisclosed amount for the nine-day trip to Brazil and Argentina for which taxpayers paid $12,000 last year. That includes $8,687 for Sanford's plane ticket, and $453 in lodging.
"I made a mistake while I was there in meeting with the woman who I was unfaithful with," the governor said in a statement.
That revelation came a day after a rambling news conference during which a pained Sanford admitted to three romantic rendezvous with the woman. Sanford spent most of his time Thursday visiting with his family at their coastal home on Sullivans Island. Asked whether he was resigning, Sanford shook his head no as he departed.
"I right now am focused on the important part of this - the family in this circumstance," he said.
His wife told reporters she was "going to worry about my family and the character of my children" and said as she left for dinner and a boat ride with the boys that her husband's career was his concern. "He'll have to worry about that," she told reporters as she drove away.
Bauer and the Sanfords have had a cool relationship.
Jenny Sanford threw her support behind Bauer's rival in a GOP primary runoff for lieutenant governor in 2006, and the governor and Bauer have disagreed over whether the state's No. 2 needs security detail. Sanford's vetoes of the funding were overridden by lawmakers.
Bauer said it was not his place to judge the governor.
"I'm not jumping on the bandwagon, immediately saying let's relieve the governor of his duties," Bauer said.
Sanford, barred by state law from running again, leaves office in 2010. If he were to resign, Bauer - expected to run for the top spot - steps into the office. Other candidates are also jockeying for the job.
"Clearly it would give me an advantage," Bauer said of a Sanford resignation. "If it weren't so, there wouldn't be so many people thinking about running for governor concerned about it."
There are deep misgivings about Bauer, though. He spent much of the 2006 campaign recovering from injuries suffered when a plane he was flying crashed. He was also injured politically by news that he had been let off for speeding after troopers stopped him. He was elected the nation's youngest lieutenant governor in 2002 at age 33.