WASHINGTON -- Tom Steyer, a billionaire environmental activist from California, wants to blast the issue of climate change to the front lines of U.S. politics: His super political action committee, NextGen Climate, will spend about $100 million this year to influence several Senate and governor's races in which climate change is seen as potentially playing a major role.

But the goal, Steyer's strategists say, is to pave the way for climate change to become a major issue in the next presidential campaign, by elevating it in the minds of voters in states that will play crucial roles in nominating and electing the next president.

Steyer's organization will pour money into media campaigns to influence Senate races in Iowa, New Hampshire, Colorado and Michigan, and governors races in Pennsylvania, Florida and Maine. The organization will back candidates who openly embrace climate-change policies to help them defeat those who question or deny the established science of climate change.

Steyer hopes those tactics will create a political landscape in which candidates fear that they will be politically punished for questioning that science. To coordinate the effort, Steyer has hired Chris Lehane, a veteran Democratic strategist.

"We want 2014 to be a pivot year for climate -- the year we can demonstrate that you can use climate change as a wedge issue to win in political races," Lehane said Wednesday at a briefing with reporters.

Lehane declined to name an exact figure, but he said Steyer had already pledged to spend $50 million of his own fortune on the effort, while NextGen Climate has committed to raising $50 million more.

This year's strategy expands on successful efforts by Steyer to elevate climate-change issues in three 2013 races. He and NextGen spent more than $11 million to influence the Virginia governor's race, with the intent of defeating Kenneth Cuccinelli, a Republican who questions the science of climate change.

Terry McAuliffe, the winning Democratic candidate, was not known as a major champion of climate policy, but he campaigned against Cuccinelli as out-of-touch and a turnoff for potential businesses seeking to invest in Virginia.

"The race in 2013 in Virginia was a beta test for 2014," Lehane said. "It provided us the political paradigm to model our other races off of."

Charles and David Koch, the billionaire industrialist brothers, have put millions of dollars into advocacy groups and super PACs like Americans for Prosperity, which have campaigned aggressively against lawmakers who support climate-change policy.

"The left knows that the global-warming agenda is a loser for them with the American people," Tim Phillips, president of Americans for Prosperity, said in an interview.

Phillips said that none of the four most vulnerable Democratic senators -- Mary Landrieu of Louisiana, Mark Begich of Alaska, Kay Hagan of North Carolina and Mark Pryor of Arkansas -- had embraced climate-change policy. All four support construction of the Keystone XL oil pipeline, which Steyer opposes.

"Senators up for re-election have their sneakers on and are running from this," Phillips said. "They know the issue doesn't matter with most Americans."

But one expert said Steyer's tactic may work.

"Independent voters, with regard to the issue of climate change, track much more closely with Democrats than Republicans," said Edward Maibach, the director of the Center for Climate Change Communication at George Mason University. "Painting candidates as climate deniers stands a good chance of working in districts where the vote turns on independents."

Steyer's group hopes to be helped by the National Climate Assessment, a new scientific report that details the ways climate change is already causing economic harm across the United States.

A Section on 05/22/2014