Americans for Prosperity, the big-spending group backed by conservative billionaires Charles and David Koch, is launching a new ad attacking Sen. Mark Pryor (D-Ark.).
"It's like living in a haze — you don't know whether you're going to have insurance or whether you're going to afford your insurance," he says in the ad.
"Mark Pryor voted for this law. He hasn't been that responsive to the issue now, you think he'll be responsive four years from now, or two years from now?"
The ad has $540,000 behind it, according to a spokesman, the latest in a deluge of spending from the group. AFP has already spent $30 million this campaign cycle, with more than half that money going into ads attacking Democrats.
Pryor is facing a tough challenge in the conservative state from Rep. Tom Cotton (R-Ark.).