(AP) WASHINGTON - Barack Obama promised to tackle climate change when he first ran for the White House four years ago, but - battling this summer for a second term - he speaks little of the issue even as the United States suffers through a drought of historic proportions, wild storms and punishing heat that.
As late as April, Obama told Rolling Stone magazine climate change would be a central campaign issue.
"I will be very clear in voicing my belief that we're going to have to take further steps to deal with climate change in a serious way," he said.
But as the campaign against Republican challenger Mitt Romney reaches an early boil, even before the parties hold their nominating conventions, climate change is little spoken of by incumbent candidate Obama, who four years ago foresaw millions of new jobs through investments in "renewable sources of energy like solar power, wind power and advanced biofuels."
Instead Obama is fighting a Romney challenge in a tight race over the struggling American economy and stubbornly high unemployment. Gallup polling repeatedly shows the economy as the chief concern among American voters at 65 percent, while environmental and pollution issues were mentioned by less than 1 percent of those polled.
Even without a big push on climate change, Obama has the support of environmentalists. Sierra Club executive director Michael Brune said Obama "has done a substantial amount in his three years to fight the climate crisis." Romney, he said, "is taking his lead from fossil fuel companies and does not even acknowledge there is a climate problem."
Romney has been accused of changing positions on the issue to curry favor with the most conservative Republicans, many of whom deny that climate change exists. As governor of the liberal-leaning state of Massachusetts, Romney imposed restrictions on carbon dioxide emissions on power plants in the state. But as a presidential candidate, he has said the "idea of spending trillions and trillions of dollars to try to reduce CO2 emissions is not the right course for us." He acknowledges that the globe is warming, but says "we don't know what's causing climate change on this planet."
Early in his administration, Obama was more bullish on tackling climate change. He pushed through tough new fuel economy standards for cars and trucks and promoted alternative energy.
But the first years of Obama's presidency were dominated by the political fight over his plan to overhaul the country's health care system. Obama managed to pass health care over intense Republican objections while Democrats controlled both houses of Congress. But after Republicans - fueled by the conservative tea party movement's anti-government, small-tax message - seized control of the House of Representatives in the 2010 elections, the president's legislative agenda has been blocked.
The United States is now more politically riven and gripped in partisanship than at any time in recent history. Legislation on a deeply controversial issue like curbing greenhouse gases stands no chance of passage in Congress at a time when Republicans are accusing Obama of reckless spending and burdening businesses with unnecessary regulations.
Obama was bitten badly when Solyndra, a solar energy firm that received a $500 million federal loan guarantee, went bankrupt and left taxpayers with the bill. Republicans painted Obama's drive for alternative energy as a waste of time and money in an economy that was struggling to pull out of the worst downturn since the Great Depression.
Obama hasn't totally ignored climate change on the campaign trail. As recently as this week he was promoting a drive to expedite seven solar and wind energy projects in the American West. His interior secretary, Ken Salazar, said Tuesday that the administration had in the past three years "approved more utility-scale renewable energy projects on public lands than in the past two decades combined."
But there is little chance that the few undecided American voters who will decide the razor-close election will cast their ballots based on the candidates' position on climate change.
James Riddlesperger, a political scientist who studies the juncture of science and politics at Texas Christian University, said the political lines are already drawn.
"Everybody already knows where the parties, the candidates stand on global warming," he said. "What is done about it awaits the outcome of this election."