Former Sen. Rick Santorum of Pennsylvania was the final challenger to Romney in the 2012 primaries (except for libertarian niche candidate Rep. Ron Paul of Texas). Mr. Santorum is now trying again, and is expected to announce his second run at the presidency on May 27.
In 2012, Santorum provided an alternative to conservatives who weren’t sure that Romney was really one of them – especially evangelical Christians who liked Santorum’s conservative Catholic faith and emphasis on social issues. Still, it may be hard for Santorum to grow his base of support in a second presidential run. But running again also may have little downside for Santorum, as it gets him back in the news and on the debate stage, thus refreshing his marketability and public image.