The following is part of a series of On Leadership profiles exploring the best leadership traits of each of the candidates in the GOP field. Our intention is to provide a debater's argument for each of the Republican hopeful's leadership strengths rather than examine the pros and cons of his overall leadership style. Click here for a full introduction to the series and links to the other candidates’ pieces.

Eighteen percentage points. That’s the margin of victory Democrat Bob Casey had over then-incumbent Rick Santorum when he trounced the two-term senator in 2006. With a loss like that, most people would pack it in for good and trade politics for private-sector riches.

But while Santorum may have made plenty of cash following his staggering loss, he’s come back to politics for more. If there’s one leadership trait Santorum has in spades, it’s his resilient and dogged persistence. Despite being largely ignored by the media and by much of the Republican establishment up until the final hours before the Iowa caucus, Santorum indefatigably plugged along through all 99 counties in Iowa, holding more than 350 town halls. “He was unbelievably disciplined,” says Michael Genovese, the director of the Institute for Leadership Studies at Loyola Marymount University and an expert on the presidency. “Nixon kept coming back, defeat after defeat, and Lincoln lost more elections than he won. There’s something to be said for that kind of resilience. He’s a workhorse.”

In a job that demands superhuman stamina like the presidency, such persistence could pay off for Santorum were he to win the nomination, which looks less likely following a poor showing in New Hampshire. Discipline is also an admirable trait for the role. Yet perhaps Santorum’s strongest leadership attribute is that he taps into a deeper sense of purpose. Almost everything the Catholic candidate believes is rooted in a set of moral values, and the idea that such principles underlie his actions and political views has helped attract followers and appeal to evangelical voters. Whether or not you agree with those values—some of them are even to the right of plenty of conservatives—there is a coherence to his platform and a consistency to his beliefs.

With the possible exception of Ron Paul, Santorum could very well win the “least likely to flip-flop” award in the current GOP field. Santorum has the reputation of being a strong-willed and quick decision maker who makes up his own mind. While that can be detrimental if enough facts or differing views aren’t considered, it also stands in contrast to the more deliberative—some believe too much so—style that has been a trademark of President Obama’s.

There’s a saying often used to describe surgeons: “Sometimes wrong, never in doubt.” For many voters, and for many Santorum supporters, the same kind of exacting, convictions-driven, self-assured approach is precisely at the heart of Santorum’s leadership appeal.

Jena McGregor writes the Post Leadership blog for the Washington Post.

Read more in this series:

Ron Paul’s best leadership trait | Rick Santorum’s best leadership trait

Newt Gingrich’s best leadership trait | Mitt Romney’s best leadership trait

Rick Perry’s best leadership trait | Jon Huntsman’s best leadership trait

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