Democratic Sen. Mark Pryor's re-election campaign made a six-figure television buy to air an ad attacking his Republican challenger, Rep. Tom Cotton, for voting to cut funding for entitlement programs.

The ad, which will air across Arkansas, hits Cotton for his past support for cuts to Social Security and Medicare as part of broader House Republican budget proposals.

The ad concludes with Pryor speaking directly to the camera, saying, "cutting waste and fraud is responsible, but cutting benefits isn't."

A spokesperson for Pryor's campaign said that line of attack would be a "major contrast theme for us going forward."

This significant ad buy by Pryor reflects the high stakes of his race, and his vulnerable position facing Cotton. Democrats and Republicans alike rank Pryor among the most at-risk Democratic Senate incumbents up for re-election in 2014.

Update: David Ray, a Cotton spokesperson, said of the ad, "Sen. Pryor is already throwing a last-minute Hail Mary pass, and the election is still 12 months away. Sen. Pryor must be scared to death that his votes for Obamacare make his re-election impossible."