Skepticism is so high that few are convinced the IRS acted alone. Sixty percent believe that other federal agencies also were used to target the tea party and other conservative groups. Ominously for Democrats, two out of three unaffiliated voters share that view.

So, why hasn’t it hurt the president’s overall job approval? Some believe it has. The theory is that with a recovering economy, his ratings should be higher. Another possibility is that the president’s base may have doubts, but they are still sticking by their man.

It also may be that the doubts are popping up in other ways. For example, at Rasmussen Reports we regularly ask voters which party they trust to deal with a range of issues including government ethics and corruption. Before the scandals broke, Democrats had an 8-point advantage on this particular issue. But there has been a 10-point swing, and the GOP now has a 2-point edge.

Among unaffiliated voters, Republicans enjoy a 23-point advantage on the ethics front. Before the controversies, it was a toss-up.