The political world is once again buzzing about evangelical Christians. Former senator Rick Santorum’s near-victory in the Iowa caucuses and his ascent in the ranks of Republican presidential contenders have fueled this new fervor, which is leading to the same tired debates and conversations that we’ve heard about evangelicals for a generation now.

Santorum’s rise in Iowa supposedly occurred because he talked about “social issues” — abortion, same-sex marriage and the breakdown of the nuclear family. But so did virtually all the other candidates. So what is it that resonates with this influential voting bloc, that propels evangelical support for one conservative candidate over another?

If you really want to understand evangelicals in America today, fix your eyes on Mile High Stadium in Denver this Sunday afternoon, when the Denver Broncos and the Pittsburgh Steelers will meet in the wild-card round of the NFL playoffs. The game will feature two star quarterbacks whose contrasting stories — one of zeal, one of redemption — reveal more about the nature, power and persistence of American evangelicalism than a caucus or primary ever could.

One of these stories is familiar by now — that of Tim Tebow, the evangelizing signal-caller for the Broncos. Tebow is a missionary’s kid, and he has a missionary’s zeal. The Heisman Trophy winner from the University of Florida has been preaching since his dad put him on a stage in the Philippines when he was 15 years old. That’s why he can’t stop thanking Jesus in every post-game interview, win or lose, and why he’s happy to pray even when the cameras are trained on him. His name has become a verb, fans wear Broncos jerseys with Tebow’s number and the name “Jesus” on the back, and his string of fourth-quarter comebacks this season seemed, well, miraculous.

But lost amid this season’s Tebow obsession has been an even more compelling tale: the deepening evangelical faith of Steelers quarterback Ben Roethlisberger. The last time Roethlisberger’s off-field actions and attitude came under scrutiny was in early 2010, when sexual assault allegations surfaced in Georgia around the two-time Super Bowl winner. Although no charges were filed, he was suspended for four games under the NFL’s personal conduct policy.

This was a far cry from the player whose first brush with NFL enforcers was over the “PFJ” (“Play for Jesus”) he painted on his cleats in his rookie year, and who in a pre-Super Bowl interview in 2005 said, “You don’t have to listen to what I have to say, but I will always have the opportunity to glorify God in all that I do.”

Instead, at the time of the allegations, many saw Roethlisberger as arrogant, a boor — anything but a man of faith. Pictures from the night he was prowling the bars in Georgia showed him wearing a T-shirt with a demon’s face on it.

Fans around the country — including many in Pittsburgh — demanded that Roethlisberger be canned, understandably so in the wake of those stories. But the Steelers kept him. They did so not only because a franchise quarterback is hard to find, but also in part because they knew the man he was when they drafted him — one who “Tebowed” before games, back when Tebowing was still known as “praying.” They knew that he came from a strong family and that he had lost his way.

And they’ve been rewarded. Quietly, and outside the media’s eyes, Roethlisberger began changing. In his only public comments after the rape allegations, and in an echo of his 2005 Super Bowl interview, he said he understood that his words were meaningless. He would have to prove that he had changed. He would have to restore his name and reputation with a new life of right action.

By the middle of 2010, he began returning to the evangelical culture of his youth — listening again to Christian artists he liked as a kid, reaching out to leaders for spiritual guidance. He joined Christ Church at Grove Farm, an evangelical church in suburban Pittsburgh. He mingled with parishioners. He dumped his entourage. His family moved in from Ohio and held him accountable for his surname. Last summer, he quietly married Ashley Harlan, who comes from a Pittsburgh family that a local pastor declared to be “one of the finest Christian families I’ve ever met in my life.”

Tebow and Roethlisberger point to the essential aspects of evangelicalism, the ones that make it persist — its missionary, proclamatory character on the one hand, and its private, searching piety on the other. The former wants to appeal to the whole world, which is why Tebow’s family raised him not only to preach, but to persuade others with a winning demeanor. The latter wants a changed life; Roethlisberger, in evangelical parlance, rededicated his life to Jesus after a period of backsliding, because he knew no other way to break his pattern of misbehavior.

In Iowa, Santorum’s evangelical “surge” grossed him about 30,000 votes. That may constitute an evangelical moment, and it may inspire some observers to define evangelicals by their political behavior. But it is not a particularly large group from which to draw conclusions about the movement as a whole. Most evangelicals, like most Americans, don’t show up to the voting booth at all. Their political commitments are not nearly as strong as their faith commitments.

Plenty of politicians attempt Tebow-like appeals; remember Texas Gov. Rick Perry’s bravado about his faith? (Perry even compared himself to Tebow at one point this fall.) That is what most people think of when they think of evangelicals and politics — a parading American moralism that uses Jesus as a rallying cry.

But what makes Tebow loved by his coaches and teammates is that it isn’t just talk. It is an authentic personal piety that can build qualities essential for football success: courage, coolness under pressure, leadership, servanthood. And that is what unites him and Roethlisberger.

It may also be what gave Santorum his breakthrough among evangelicals in Iowa. Quietly, from town hall meeting to pizza joint to pancake house, he shared his vision for the country, but he also told his own story — the blue-collar working family that was his foundation, the wife who is his love, the daily dependence on God, the daughter with the genetic ailment that should have already killed her. He came across more as a pilgrim than a politician. (If he repented during this tour, it was probably for having served in the Senate.)

Other politicians who want to appeal to the evangelical electorate would be wise to lower their own protective shields and speak from the heart about their struggles and need for God — if, and only if, they can do so truly and honestly. Evangelical piety depends on sincerity. President George W. Bush shared his journey of alcoholism and redemption time after time; evangelicals believed him because they recognized the story as true — indeed, as their own story.

But remaining a pilgrim in the world of politics is hard. It is far easier on the football field, where success requires one to play for something larger than oneself. Politics, rightly played, has the same requirement. But when was the last time we saw a politician subordinate his or her interests to those of a greater cause?

Tebow is a missionary. Roethlisberger is a prodigal son come home. Both men have found ways of living their faith — of being Christian pilgrims — that reveal more about evangelicalism than whatever can be gleaned from Iowa exit polls. As they take the field Sunday, anyone wanting to know what makes evangelicals tick would be wise to pay attention.

After all, evangelical voters may identify with a politician for a short season, but this is fleeting. Their loyalty is not to politics or party, but to their faith.

David Kuo, a Steelers fan, was deputy director of the Office of Faith-Based and Community Initiatives in the George W. Bush White House and is the author of “Tempting Faith: An Inside Story of Political Seduction.” Patton Dodd, a Broncos fan, is managing editor of Patheos and the author of “The Tebow Mystique: The Faith and Fans of Football’s Most Polarizing Player.”

More on Tim Tebow, faith and politics:

What Tim Tebow’s Super Bowl ad can teach the pro-choice movement

Tim Tebow: Evidence of things unseen

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