Mitt Romney asked Thursday where all the "hope and change" has gone, as President Obama's supporters pressed ahead with plans to air a misleading TV ad and a top campaign aide was accused of "lying" about her knowledge of its contents. 

The Republican presidential candidate, in his most forceful comments to date, suggested Obama's supporters should be "embarrassed" over the super PAC ad that ties him to a woman's death from cancer. But he wasn't holding out hope that the group would pull it down, after the Democratic operative behind the ad claimed it'll be airing soon in battleground states despite the furor.   

"You know, in the past when somebody pointed out that something was inaccurate campaigns either pulled the ad - they were embarrassed," Romney said on Bill Bennett's "Morning in America" radio show. "Today, they just blast ahead." 

The Obama campaign has faced mounting criticism over the ad not just from Romney but independent fact-checkers, though the ad was produced by the purportedly independent super PAC Priorities USA.