Republican presidential candidate John McCain hopes to enhance his appeal to blue-collar voters and those in the Northern Plains by visiting the Sturgis Motorcycle Rally in South Dakota.

McCain, who attended the rally's tribute to veterans on Monday night, was greeted in Rapid City by Sen. John Thune, who has been mentioned as a possible running mate.

Earlier in the day, he called on Congress to return from its summer recess to deal with the nation's energy crisis. And he urged his Democratic opponent, Barack Obama, to join him in that call.

On Friday, the House and Senate, both controlled by the Democrats, adjourned for five weeks without taking up energy legislation.

"Congress should come back into session, and I'm willing to come off the campaign trail," McCain said at the Lafayette Hill, Pa., headquarters of the National Label Co.

The visit to National Label was McCain's only stop during a stay in the Philadelphia area that lasted about four hours. He toured the facility, which makes labels for pharmaceuticals and other consumer products, and held a closed, half-hour roundtable with business executives.

With about 100 of the plant's workers standing behind him, McCain said that the way to address the nation's energy needs is through an "all-of-the-above approach" of utilizing nuclear power, clean coal technology and additional off-shore oil drilling.

After criticizing Obama's energy policy, McCain added: "We're not going to achieve energy independence by inflating our tires."

Last week, Obama said the nation could save all the oil it would add through more off-shore drilling if only drivers were "making sure your tires are inflated" and getting tune-ups. That comment has drawn ridicule. The McCain campaign is now offering supporters tire gauges labeled "Obama Energy Plan" in exchange for $25 donations.

An Obama spokesman pointed Monday to a Department of Energy directive that said that driving with proper tire pressure and wheel alignment improves mileage by 3.3 percent -- and to statements by NASCAR and by California Gov. Arnold Schwarzenegger, a Republican, urging motorists to heed such advice.

One reason McCain continues to pound away at the energy issue is that polls show it to be a winner for him, as Obama has acknowledged. Surveys in several swing states show that voters favor expansion of nuclear power and off-shore oil drilling by about a 2-1 ratio.

McCain's campaign staff said the roundtable was designed to highlight his concern for small business. Among the elements in his plan on that score -- beyond reduced energy costs -- are cutting the corporate tax rate from 35 to 25 percent and establishing a permanent tax credit for research and development.

Today, to underscore his call for expanded U.S. nuclear power, McCain will tour a nuclear power plant in the battleground state of Michigan.

The Associated Press contributed to this report.