Nicole Bengiveno / The New York Times / Redux Businessman Foster Friess introduces Republican presidential candidate Rick Santorum to the stage at the Conservative Political Action Conference in Washington, Feb. 10, 2012.

For the past several weeks, few people have been enjoying the Republican presidential campaign quite as much as Foster Friess. The 71-year-old mutual fund millionaire from Wyoming, who has emerged as the key backer of Rick Santorum’s super PAC, has taken advantage of the access his largesse affords by joining the candidate on the campaign trail. While a Santorum surge began stirring in the Iowa cornfields, Friess was a passenger in the gunmetal Dodge RAM — nicknamed the “Chuck Truck,” because it belonged to local supporter Chuck Laudner — that schlepped Santorum around the Hawkeye State. On Election Night, he bounded into the Stoney Creek Inn in Johnston, Iowa, to regale reporters with tales from the caucus site he’d visited. Asked if he was enjoying himself, Friess beamed, “If I was any better I’d be an astronaut. It’s one of the most incredible experiences of America I’ve ever had.”

On Feb. 7, he was back standing over Santorum’s right shoulder as the candidate addressed a suburban St. Louis ballroom on the night Santorum’s three-state sweep vaulted him back into the thick of the GOP nomination fight. Three days later, he was tapped to introduce Santorum for the candidate’s address at CPAC. “Life is just so much fun and so filled with humor,” began the snowy-haired financier, clad in a sweater vest of his own. “There’s a little bar a couple doors down and recently a conservative, a liberal and a moderate walked into the bar.” Pause a beat. “The bartender says, ‘Hi Mitt!'” As the crowd cheered, Friess busted out into laughter at his own joke.

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Now Friess’s sense of humor has gotten him into hot water. During an interview Thursday with MSNBC’s Andrea Mitchell, Friess was asked about Santorum’s stance on social issues, including comments he’s made about contraception. His reply: “We maybe need a massive therapy session so we can concentrate on what the real issues are. And this contraceptive thing, my gosh, it’s such inexpensive. Back in my days, they used Bayer Aspirin for contraceptives. The gals put it between their knees and it wasn’t that costly.” Within minutes, the remark ricocheted around the Internet. Friess quickly arranged a nighttime appearance to quash the hubbub. And Santorum was forced to distance himself from his biggest patron. “I’m not responsible for every comment that a supporter of mine makes,” the former Senator told Charlie Rose. “It was a bad joke. It was a stupid joke. It’s not reflective of me or my record.”

The kerfuffle may dull the enthusiasm Friess has thus far evinced on the campaign trail. But it’s not likely to affect Friess’s relationship with Santorum. In an email to TIME this week, Friess said he had gained an appreciation for Santorum’s empathy and bearing while traveling with the candidate on the campaign trail. “There is a deep-seated kindness and love for other people, particularly the blue-collar, non-elitist folks that he so identifies with,” Friess says. “People gravitate to him because of his authenticity and the way he answers questions directly…People like him, believe he’s honest, and share his core values about what makes America great.”

Friess shares many of those core values, including Santorum’s emphasis on the importance of his faith. In 1978, when he was nearing 40, and struggling to balance his business success with his fraying family relationships, Friess became a Christian. “I did one of those ‘born again’ things and invited Jesus to become the ‘Chairman of the Board,'” he writes on his website, titled “Man Atop the Horse.”

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Friess has deep ties to conservative Christian causes, and invokes their shared faith as one of the things that underpin his support of Santorum. “What strikes me about Rick is that he truly embraces the Corinthians 13 admonition,” he says. “He has absolutely no hate toward [people who protest his views.] He actually prays for those who persecute him.”

Though he’s only now vaulting to national prominence, the cowboy-hatted investor has been a renowned donor in conservative circles for some time. According to FEC records, he’s ponied up well more than $1 million to conservative politicians. He’s also given millions to the Daily Caller, a Washington-based conservative website, as well as to charities. The Guardian reported that Friess and his wife forked over $5 million to aid relief efforts after Hurricane Katrina, the Haitian earthquake and the Asian tsunami.

Friess’s financial support for Santorum dates back at least to 1997. But in recent months he’s emerged as the single most influential figure in sustaining Santorum’s shoestring campaign through lean times. According to FEC records, as of Dec. 31, he had given $331,000 to the Red, White and Blue Fund, a Santorum-allied super PAC, and he’s indicated that more will likely be on the way. “My contribution level will be revealed soon, but even if it’s a million dollars, that’s really not much of a sacrifice when you think of these young 18- and 19-year-olds strapping a gun on their back and going off to Afghanistan and Iraq to protect the freedoms we cherish,” he says.

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