As Minnesotans head into the first Independence Day holiday in history with gas station signs reading $4 per gallon, Senate candidates Norm Coleman and Al Franken traded ideas -- and a few shots -- Wednesday about how to bring down pump prices in the short run and end long-term dependency on foreign oil.

Coleman, the Republican incumbent, toured a printing plant near downtown St. Paul, where he assured workers that after getting their "ears chewed by constituents" over the July 4th recess, his colleagues will return to Congress next week determined to pass a comprehensive energy plan that expands offshore drilling, increases nuclear energy and promotes development of renewable sources.

If the energy problem is attacked on a wide number of fronts, he said, "you'd have an impact on speculation which would lower some of the [gas] price immediately, even though the technology itself may not be operational until the future."

DFL challenger Franken, who has talked since last year about an Apollo project-style program to develop renewable energy sources and promote greater efficiency, told reporters that the kind of drilling Coleman was promoting wouldn't bring down prices for years.

Franken's short-term strategy: Remove tax subsidies for oil companies and use the money instead for alternative-energy research, and drill in the millions of acres already leased by oil companies that aren't being used. He labeled as "phony" Coleman's plan to bring down prices by drilling on the outer continental shelf.

Franken also said that, given the historic increase in gas prices, he no longer thinks lawmakers should consider raising the gas tax.

"I said I would put it on the table only as a last resort, because we had fallen behind in infrastructure," he said. "Now, I've completely taken it off the table, because gas is $4 a gallon and people are hurting."

Coleman chided Franken for what he called "a flip" on the gas tax. "He was wrong [about raising the gas tax] when it was at $2 a gallon and $3 a gallon, and the fact that it took him to get to $4 a gallon says he's just out of touch," Coleman said.

Coleman and the DFL continued the debate Wednesday on whether the senator's $600 monthly rental payment is the fair market price for the garden-level bedroom and bathroom he rents from a Republican associate in Washington.

Coleman said that Internet rental listings for similar apartments in the area prove he's not getting a deal, and added that he welcomes further scrutiny.

DFL Party Chair Brian Melendez, on the other hand, said Wednesday that the only $600 apartments they've been able to find in the area were either shared quarters or places much farther than Coleman's residence from the Capitol.

Kevin Duchschere • 612-673-4455