Sen. Mark Pryor is once again defending Obamacare in a TV ad without naming it, doubling down on a campaign strategy that Republicans criticized him for in a key Senate race.

In a new ad released today, the Arkansas Democrat argues that his vote for the law helped cut waste in Medicare and protected benefits for seniors.

“I’m Mark Pryor and I approve this message because making sure seniors get the health care they need is responsible. Overpaying insurance companies isn’t,” the ad concludes.

It was the second ad in which he has touted some of the benefits of the Affordable Care Act, which he voted for in 2010. But as with a previous ad which began airing two weeks ago, Pryor did not name the law.

After the first ad ran, the Karl Rove-led Crossroads GPS attacked Pryor with its own spot which specifically called him out for not naming the Affordable Care Act in his defense.

The dueling ads are the most high-profile example of Obamacare being used as a campaign issue this election cycle, especially by a Democrat.

The law remains broadly unpopular, with 53 percent of Americans saying they viewed it unfavorably in an August tracking poll by the Kaiser Family Foundation.