Campaign officials confirm that Mr. Obama’s Chicago-based organization has begun combing through the former Pennsylvania senator’s background, looking for possible lines of attack. It also emailed Mr. Obama’s Pennsylvania supporters this past week asking for material that could be used against Mr. Santorum.
Mr. Romney, a former Massachusetts governor, still leads the delegate race. But after capturing caucuses in Minnesota and Colorado and a nonbinding primary in Missouri on Feb. 7, Mr. Santorum has enjoyed a burst of attention. Several polls also have given him a lead in Mr. Romney’s native Michigan, where primary voters cast ballots a week from Tuesday.
Romney co-chairman in Arizona steps down
Pima County Sheriff Paul Babeau, who is running for Congress in Arizona, resigned from Mr. Romney’s campaign after the Phoenix New Times, an alternative weekly magazine, reported that Mr. Babeau had threatened to deport the man, a Mexican immigrant, if he revealed the nature of the relationship.
Sheriff Babeau held a news conference Saturday and acknowledged he is gay. He denied the allegations of misconduct.
“Sheriff Babeau has stepped down from his volunteer position with the campaign so he can focus on the allegations against him. We support his decision,” Romney spokeswoman Andrea Saul said in a statement.
Sheriff Babeau, who has risen to national prominence with his strong opposition to illegal immigration, campaigned with Mr. Romney and was featured in robocalls in Iowa attacking Texas Gov. Rick Perry, who was then running for the GOP nomination. He said he’ll continue his congressional campaign in Arizona.
The allegations come as Mr. Romney is fighting to win the Feb. 28 primary in Arizona. He is the only candidate who is making a strong play in the state, although rival Rick Santorum and his allies have spent some money on TV ads. The GOP contenders will debate in the state next week.
Sheriff Babeau’s campaign manager, Chris DeRose, said Sheriff Babeau’s congressional campaign was notified Friday afternoon about the allegations and that they immediately consulted the Romney campaign. Mr. DeRose said Sheriff Babeau offered to step down from his role as campaign co-chairman.