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President Bush, Arizona Sen. John McCain and a slew of other Republican lawmakers are calling to lift the ban on offshore drilling, but that's not the only place they're hoping to uncover oil. Some Rocky Mountain states, including Wyoming, Utah and Colorado, are also under the spotlight after Bush pushed Wednesday to harvest oil from shale found in the region.

Just the thing to add fuel to the fire in a heated race between the two Colorado Senate candidates, former congressman and current energy executive Bob Schaffer (R) and Rep. Mark Udall (D). The League of Conservation Voters, an environmental advocacy group, is up with a new ad (subscription) scrutinizing Schaffer's track record with oil companies.

"In Congress, Bob Schaffer voted to give $13 billion in tax breaks to gas and big oil," an announcer says in the ad. "Schaffer then became an executive at a big oil company and went to Iraq to secure a contract for Iraqi oil. So it’s no surprise that Schaffer’s campaigns have taken $150,000 from gas and big oil." The 30-second spot reiterates claims the organization put forth in another ad (subscription) at the end of May.

"What we’re doing with these ads is presenting the evidence of where he [Schaffer] has been and what he’s done in the past and let the voters decide for themselves if he is going to represent Colorado or the oil companies if he gets to Washington," said LCV spokesman Joshua McNeil. He also praised Schaffer's opponent, Udall, for being a "real environmental champion throughout his time in Congress."

Tony Massaro, political director for LCV, said that although the group isn't against drilling in Colorado entirely, it shouldn't be the only solution. "We look at Schaffer as a person who will consistently work on the positions of the oil and gas companies, which I think involves dramatically accelerating already aggressive drilling that’s going on in Colorado," he said.

The organization plans to continue to closely follow this contest, as well as the Senate races in New Hampshire and New Mexico, because of key candidates' stances on LCV's priority issues, such as renewable energy and global warming, Massaro said. The group will not be alone in its scrutiny -- according to Hotline's new rankings (subscription) of the Senate seats most likely to switch party control in November, those three states round out the top four (behind No. 1 Virginia).