LORDSTOWN, Ohio -- On a day when world oil prices gushed to yet another record, Sen. John S. McCain highlighted his proposals to diversify the nation's energy resources as he toured the giant General Motors plant here.

As he did, his campaign was launching a new national television campaign advertising the Lexington Project, as he has dubbed the litany of ideas he has advanced to promote alternative energy sources and curb the nation's dependence on foreign oil.

The Republican presidential candidate dismissed criticism of one aspect of the project -- that a promised $300 million award for new battery technology is a "gimmick" -- noting that Charles Lindbergh's historic New York to Paris flight had been spurred by a similar cash prize.

He repeated his goal of seeking 45 new nuclear plants across the country while promising billions in subsidies to the development of clean coal technology. Mr. McCain noted that the output of both new coal- and atomic-fired plants will be needed if companies such as GM move toward vehicles that rely on electricity rather than oil.

During the state's Democratic primary campaign in Ohio, both candidates tried to exploit dissatisfaction with the North American Free Trade Agreement and other trade accords. In answer to a question at a brief town hall session with plant employees, however, Mr. McCain reiterated his commitment to free trade but said that he was open to reviewing the enforcement mechanism of such treaties.

At a subsequent news conference he rejected the idea of "a classic bailout," for American auto firms struggling with the effects of rising fuel prices and foreign competition. He said, however that he would promote and encourage federal assistance to help pay for the costs of research into new technologies.

During a similar tour of this plant before the state's primary, Sen. Hillary Rodham Clinton, who carried the state, had said she would support federal assistance to prevent a bankruptcy by one of the Big 3 automakers.

Mrs. Clinton was campaigning in New Hampshire today, affirming her loyalty to Mr. Obama in the primary rivals' first joint campaign appearance since Mr. Obama secured the Democratic nomination.

Mr. McCain said he hoped to peel off at least some of the support from the unsuccessful candidate who had preceded him here.

"I do think we are able to attract some of Sen. Clinton's supporters, not so much because of any reason than that they think that I may serve America best," he said. "I had a woman at a town hall meeting yesterday at Xavier [University in Cincinnati] who was wearing a Hillary hat; I was pleased that she was there."

Mr. Obama said he would be back in Ohio many times between now and the November election, noting that no president since John Kennedy had reached the White House without winning Ohio.