The extended Republican primary circus is taking a toll on frontrunner Mitt Romney, who is now less popular even than former President George W. Bush, according to a poll released Thursday afternoon.

The new survey from Public Policy Polling shows that Romney is viewed favorably by 33 percent of voters, whereas a healthy majority of 58 percent view him unfavorably. Bush does far better, at 45 percent favorable and 46 percent unfavorable. The former president has seen something of a rehabilitation in his image since he left office and memories of his administration have begun to fade, but for him to be stronger than Romney among independent voters just a few years after an economic meltdown and disaster in Iraq is striking.

To be sure, the GOP debate has shifted in recent months to terrain friendlier to Democrats, including wealth, inequality, and contraception, which probably explains independents souring on Romney. But the data show that much of Mitt’s trouble remains in his own party base; 79 percent of Republicans view Bush favorably, but only 49 percent feel that way about Romney. And a campaign adviser comparing the shift in Romney’s positions between the primary and general elections to an “etch a sketch” toy won’t do much to help.