Rep. Cory GardnerCory Scott GardnerSenate moving ahead with border bill, despite Trump 13 GOP senators ask administration to pause separation of immigrant families Sessions floats federal law that would protect states that decriminalize marijuana MORE (R-Colo.) is continuing his play for female voters with a new ad that highlights his proposal to offer certain types of birth control without a prescription.

It’s his latest effort in his battle with Sen. Mark UdallMark Emery UdallSenate GOP rejects Trump’s call to go big on gun legislation Democratic primary could upend bid for Colorado seat Picking 2018 candidates pits McConnell vs. GOP groups MORE (D) to pitch his campaign directly to women, a key voting bloc that will be pivotal in deciding the outcome of the race.

In the ad, Gardner tells a group of women that the “difference” between him and the senator is that “I believe the pill ought to be available over the counter, round the clock, without a prescription — cheaper and easier, for you.”

“Mark Udall’s plan is different,” he adds. “He wants to keep government bureaucrats between you and your healthcare plan. That means more politics, and more profits for drug companies.”

Gardner endorsed the idea of providing certain forms of birth control over the counter in a June op-ed that argued such a move would make contraception cheaper and more accessible for all women.

But Udall’s campaign pushed back on Gardner's ad, noting Gardner’s support for a federal “personhood” measure that would effectively outlaw abortion and ban certain forms of birth control, as well as his previous votes in favor of measures that would allow employers to deny coverage for contraception.

Udall campaign spokeswoman Kristin Lynch said the ad was an attempt to “hide his backwards agenda from Colorado women.”

“The undeniable fact is Gardner continues to push radical, anti-woman measures that would ban common forms of birth control. One 30-second ad doesn’t make up for that,” she added.