The ad is the second in a trio the group is running in the state, backed by a significant $320,000 ad buy.
The organization often backs conservatives in GOP Senate primaries, but it and the Club for Growth have been spending much of their early money ripping Pryor. That money seems designed to entice Rep. Tom Cotton (R-Ark.) to jump in the race, which Cotton is expected to do.
The Democratic Senatorial Campaign Committee fired back, accusing Shroyer and the group of hypocrisy because Shroyer's company took federal stimulus funds.
"Typical arrogance and hypocrisy from Tom Cotton and his allies in Washington," DSCC spokesman Matt Canter said in a statement. "They never let actual facts get in the way of their arguments. Cotton and his allies need to understand that Arkansans expect their public servants to be honest and thoughtful – not misleading and hypocritical."
Cotton was not involved with the ads.
Pryor, who is one of the most vulnerable incumbent senators up for reelection this cycle has been taking fire from both sides: A group backed by New York City Mayor Michael Bloomberg (I) has also been running ads criticizing him for his vote against firearm background check legislation.
The senator has gotten some support in recent days, however: Sen. Tim Kaine (D-Va.) sent a fundraising email on his behalf Tuesday night.
This post was last updated at 3:20 p.m.