WASHINGTON (AP) — Former presidential hopeful Rick Santorum urged his supporters to back fellow Republican Mitt Romney’s campaign Monday in a late-night email that ignored that Santorum once calling Romney the “worst Republican in the country” during their bitter contest.

Santorum, a former senator from Pennsylvania and a newly minted celebrity among conservatives, said that the one-time rivals would unite to deny President Barack Obama’s re-election. But in a nod that the wounds had not yet healed, he reminded his supporters of the deep differences between the two and that misgivings had not yet abated.

“The primary campaign certainly made it clear that Gov. Romney and I have some differences. But there are many significant areas in which we agree,” Santorum wrote, citing common ground in economic, social and foreign policy.

He added: “Above all else, we both agree that President Obama must be defeated.”