Former Sen. Rick Santorum at the 2015 NRA Annual Meeting & Exhibits in Nashville, Tennessee on April 10, 2015. National Journal

This article is from the archive of our partner National Journal

In Republican presidential primaries, the candidate who finished second last time usually begins as a front-runner when they run again.

That's not the case with Rick Santorum, who on Wednesday will announce he's once again running for president in an ABC New interview.The former senator from Pennsylvania begins his second campaign for the presidency as a prohibitive underdog, struggling to win back primary voters who have moved on after his runner-up finish to Mitt Romney.

Polls show Santorum trailing far behind the leading candidates in Iowa, whose caucuses he won in 2012, and he barely registers in national surveys of the primary. He's drawing little early support from major donors and even his social conservatives, the voters who regard Santorum most highly, have shown more interest in alternatives like former Arkansas Gov. Mike Huckabee and Texas Sen. Ted Cruz.

The candidate who left public office in 2007 suffers the most from the perception that he's been eclipsed by a new generation of Republicans, like Sens. Cruz, Rand Paul, Marco Rubio, and Gov. Scott Walker. Not only did Santorum lose his post in the Senate nearly a decade ago, he did so after losing his re-election by nearly 20 points. At the time, Santorum was considered too socially conservative to win over middle-of-the road voters who decide general elections, a perception that will continue to haunt his candidacy now.

Still, Santorum and his advisers feel they are in much better position now than they were for the 2012 campaign, with enough money and name recognition to build the kind of full-fledged professional campaign they couldn't previously.

And Santorum wants to rebrand himself not as a culture warrior but as a spokesman for the working class. He's built a platform that includes plans to reduce legal immigration while, rhetorically, accusing both parties of leaving blue-collar workers behind. Santorum's contention is that, as a native of hardscrabble Western Pennsylvania, he can bring those voters back into the Republican Party.

How successful he is could determine whether he's able to match, or even come close, to his second-place result of last primary.

This article is from the archive of our partner National Journal.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.