The electoral energy wars have raged from Florida — where Mr. McCain has proposed offshore oil drilling — to California and now Las Vegas. The candidates are trying to define how they would tackle the sharp spiral upward in gasoline prices and its ever more severe impact on the economy, and so far their policy proposals are poles apart.  Mr. McCain emphasizes greatly expanded drilling, offshore and on public lands. And he would revitalize the nearly moribund nuclear power industry, noting that France draws much of its energy from nuclear plants.  He suffered a bit of an embarrassment on Tuesday in Santa Barbara, Calif., as he heard his own invited panelist, Michael Feeney, executive director of the Land Trust for Santa Barbara, worry aloud about offshore drilling. “It makes me nervous to think about those who are proposing to drain America’s offshore oil and gas reserves as quickly as possible in the hopes of driving down the price of gasoline,” Mr. Feeney said.  Mr. McCain noted that Republican governors were divided on his proposal, with Gov. Arnold Schwarzenegger of California opposed and Gov. Charlie Crist of Florida in favor.  Mr. Obama illustrated the gap between the candidates by giving a speech at a water plant in Las Vegas that laid heavy emphasis on $150 billion worth of alternative energy, including wind and solar power and hoped-for clean coal technology (Mr. Obama acknowledged, in response to a question, that he was not ruling out nuclear power, but he strongly suggested it was a distinctly lower priority). He asserted that these investments in technology would yield five million new jobs.  He also proposed to charge oil companies an undefined fee for every acre that they lease but fail to drill on. Oil companies now lease but are not drilling on about 68 million acres, according to the Obama campaign.  “If that compels them to drill, we’ll get more oil,” Mr. Obama said. “If it doesn’t, the fees will go toward more investment in renewable sources of energy.”  The goal, Mr. Obama said, would be to catch and replicate the success of the world leaders in this field.  “Germany, a country as cloudy as the Pacific Northwest, is now a world leader in the solar power industry and the quarter-million new jobs it has created,” Mr. Obama said. “To truly harness its potential, we urgently need real leadership from Washington — leadership that has been missing for decades.”  He also poked fun at Mr. McCain’s proposals, specifically his suggestion to establish a $300 million prize for the scientist who could come up with a long-lasting car battery. “When John F. Kennedy decided that we were going to put a man on the Moon, he didn’t put a bounty out for some rocket scientist to win,” he said. “He put the full resources of the United States government behind the project.”  Mr. McCain lashed back at Mr. Obama when speaking in Riverside.  “On this energy issue, yeah, it’s easy to say ‘no’ to everything,” Mr. McCain said. “That’s what Senator Obama is doing. We’ve got to come forward with bold proposals, innovative ones, and ones that will bring this nation to energy independence for national security reasons as well as others.”  Michael Powell reported from Las Vegas, and Michael Cooper from Santa Barbara, Calif.  A version of this article appears in print on , on Page A16 of the New York edition with the headline: Obama and McCain Joust Over Oil Drilling. Order Reprints| Today's Paper|Subscribe
Barack Obama took a poke at John McCain on Tuesday, saying that for him to talk of a “psychological benefit” from expanded offshore drilling is to define that policy as a gimmick.