Tom Steyer is standing upright near the corner of a small, beige meeting room at Georgetown University, arms at his sides, eyes shut intently. Half a dozen ministers and priests surround him, laying hands on his torso.

Together, the pastors begin to pray, asking for divine help in shaping public opinion: "Soften them.... Open them to you … for your purpose.... Claim the promise made to Moses."

It is a curious warmup for a technical conference about an oil pipeline.

But like many other environmentalists concerned that America is dawdling as the world burns, these ministers, each a leader in efforts to mobilize churchgoers against climate change, see Steyer as, quite literally, a godsend.

Heady stuff, even for a 56-year-old billionaire.

For years, liberals have fretted about the power of ultrawealthy people determined to use their billions to advance their political views. Charles and David Koch, in particular, have ranked high in the demonology of the American left.

But in Steyer, liberals have a billionaire on their side. Like the Kochs, he is building a vast political network and seizing opportunities provided by loose campaign finance rules to insert himself into elections nationwide. In direct contrast to them, he has made opposition to fossil fuels and the campaign against global warming the center of his activism.

The former financier is an unlikely green icon. Steyer built his fortune with a San Francisco-based hedge fund of the sort that drove protesters to occupy Wall Street. Some of the investments that landed him on the Forbes list of America's wealthiest went into companies he now says are destroying the planet. Adversaries and, in private, at least some erstwhile allies call him a dilettante.

Yet, unlike many others in a parade of super-rich Californians who have made forays into politics, Steyer has proved himself skilled at bringing attention to his cause and himself.

He has amassed impressive victories: helping persuade recession-weary Californians to pass a $1-billion annual tax hike; creating a gusher of money for energy efficiency; and this year playing a star role in destabilizing plans for the Keystone XL Pipeline with a campaign that has sown doubt about the project inside the administration and mobilized influential Democratic donors and business leaders against it.

Opponents of the pipeline, designed to move hundreds of thousands of barrels of oil daily along a 1,200-mile route from Canada's tar sands to Gulf Coast refineries, say it would contribute greatly to global warming.

"Normally, in the American system, people yell and scream and holler and nothing happens, and then something happens and it gets fixed," Steyer said in a recent interview. "That happened with acid rain, with the hole in the ozone layer. That is normally what happens."

Global warming, "for whatever reason, was not getting addressed," he said. "And it is the biggest issue."

It was Keystone that brought Steyer and the pastors together at Georgetown. In June, President Obama said in a speech at the university that he could approve the pipeline project, which needs a federal license because it crosses an international boundary, only if backers could prove it would not contribute to global warming.

Six months later, Steyer returned to the campus with a panel of anti-Keystone scientists to host a conference aimed at proving that test could not be met.

John Podesta, President Clinton's former chief of staff, who recently joined the Obama White House as a senior advisor, says he used to give Keystone a 90% chance of winning approval from the administration. Then Steyer and grass-roots activists like Bill McKibben of 350.org launched their campaigns against it. Now, he gives it even odds, Podesta said in an interview shortly before his new post was announced.

"I doubt the president travels very much where he doesn't hear about this now, particularly with core supporters," Podesta said. "What he hears has got to make him take a few deep breaths before moving forward with it."

Steyer "is good at organizing the people the president knows and cares about," he added.

Defenders of the project call Steyer and fellow anti-Keystone activists misguided.

"It is an absolute calamity that it was not approved long ago," former Secretary of State George P. Shultz said of the Keystone project. Shultz was Steyer's co-chairman on the $1-billion tax hike campaign and another successful effort to protect California's global warming law against a ballot initiative, but he disagrees deeply with Steyer about the pipeline.