The TV spots released this week come in a close race against Democratic Sen. Mark Udall in a swing state that has become increasingly reluctant to elect conservatives as coastal transplants have pushed the politics to the left.
Democrats have won every top-of-the-ticket statewide race in Colorado since 2004, and Udall and his allies have followed the established playbook by attacking Gardner as being against reproductive rights and the environment.
But Gardner, a U.S. House representative, has hit back with his new ads.
In the first, which launched Monday, Gardner walks past wind turbines and asks, "So what's a Republican, like me, doing at a wind farm?" He notes that he co-authored legislation, backed by a former Democratic governor, to create a state agency to support new Colorado renewable energy businesses. The ad's female narrator calls Gardner "a new kind of Republican."
Then, in a spot unveiled Tuesday, Gardner, who is anti-abortion, highlights his proposal to make birth control pills available without a prescription. Gardner tells a mostly-female audience in the ad that Udall "wants to keep government bureaucrats between you and your health care plan."
Gardner's campaign and other conservatives say the congressman is responding to a Democratic caricature of his positions.
But Democrats say Gardner is trying to sell himself as a centrist in the line of Udall, a well-known environmentalist and abortion rights supporter.
They noted that Gardner's birth control ad comes after Udall and others hammered him for his prior support of measures that could outlaw some forms of birth control. Gardner has since disavowed one of the criticized proposals.
"Unlike Congressman Gardner, I don't see access to contraception and family planning services as election-year gimmicks," Udall said in a statement. "They're fundamental rights that we must protect. And Coloradans know that I'll do just that."
Seth Masket, a political scientist at the University of Denver, said Gardner's ads are clearly "on Democratic turf" but changing positions and emphasis may not be damaging.
"It's easy to attack a candidate who does that as a flip-flopper" but there's not much evidence showing that to be politically damaging, Masket said. However, "taking a wrong stance on an issue important to voters can hurt a candidate," he said.
Republicans need to net six Senate seats in November to win control of the chamber.
Most polls show Gardner is effectively tied with Udall, with the Democratic incumbent maintaining an edge among women.
Women not registered with either party in the Denver suburbs usually decide statewide elections in Colorado and both campaigns are furiously trying to appeal to that demographic.
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