With a gas pump doubling as a campaign prop, Senate candidate Connie Mack launched a petition drive Thursday at a Miami gas station to call for the building of the politically charged Keystone XL pipeline.

Mack, a Republican Congressman from Fort Myers, said the high cost of fuel at the Mobil gas station on Coral Way was, essentially, the fault of the president and Democratic Sen. Bill Nelson for opposing the pipeline.

“These are two lockstep liberals who apparently don’t believe in our energy supply here in the United States,” Mack, brandishing his petition, said. “They don’t believe lower gas prices are important.”

But the only man who signed the petition, gas station owner Michael Mendez, didn’t sound so sure about what the pipeline would do or how much President Obama or Nelson were to blame for the costs of oil, which Mendez said was a global issue.

“These gas prices, to me, it doesn’t matter who’s in office,” Mendez said. “Gas prices always go up throughout the year. And then it’s going to come down. And then everyone’s not going to say anything for a little while.”

Still, Mendez said, the petition is “better than doing nothing.”

Mack’s criticisms of Obama and Nelson reflect a nationwide push by Republicans who see the rising fuel prices as hampering economic growth — and therefore the approval ratings of the president. Mack has pushed for the pipeline for more than a year.

Still, a recent Florida poll showed that voters largely blame oil companies and global market forces for the prices at the pump.

Nelson’s office declined to comment, but Democrats note that they tried to link the approval of the pipeline with a requirement that the oil be sold in the United States. Senate Republicans rejected the proposal.

Democrats then voted last month against the pipeline, which would carry oil from Canadian tar sands 1,700 miles to refineries in the Gulf. Obama personally lobbied some senators, according to some reports, largely because his administration believes the pipeline needs more environmental study.

“After getting a call from his good buddy Obama and being a yes man for Obama, he sided with the liberals and voted no,” Mack said.

Nelson has blamed the high price of oil on commodities speculators.

Mack said the senator is ignoring the fact that the price of commodities goes up when speculators believe there’s a dwindling supply — the result of the Democrats’ opposition to the pipeline, oil drilling off Florida’s shores and exploration in the Arctic National Wildlife Refuge, nicknamed “anwar.”

Nelson is staunchly opposed to offshore drilling, citing the BP spill in 2010. Mack has a different view.

“I have always said that I would be for drilling,” Mack said. “But I think that’s an issue the state should have a say in — in determining how far it’s going to be off the coast of Florida. We ought to allow the state to have a say in that decision.”

To read more, visit www.miamiherald.com.