Mitt Romney's aides explained with unusual political bluntness today why they are spending heavily — and ignoring media criticism — to air an add accusing President Barack Obama of "gutting" the work requirement for welfare, a marginal political issue since the mid-1990s that Romney pushed back to center stage.

"Our most effective ad is our welfare ad," a top television advertising strategist for Romney, Ashley O'Connor, said at a forum Tuesday hosted by ABCNews and Yahoo! News. "It's new information."

The welfare ad has been the center of intense dispute, with Democrats accusing Romney of unearthing old racial ghosts and Romney pointing out that the Obama Administration has offered states waivers that could, in fact, lighten work requirements in welfare, a central issue in Bill Clinton's 1996 revamping of public assistance.

The Washington Post's "Fact Checker" awarded Romney's ad "four Pinocchios," a measure Romney pollster Neil Newhouse dismissed.

"Fact checkers come to this with their own sets of thoughts and beliefs, and we’re not going to let our campaign be dictated by fact checkers," he said. The fact-checkers — whose institutional rise has been a feature of the cycle — have "jumped the shark," he added after the panel.

Romney's aides have brushed off suggestions the welfare fight has a racial edge.

His longtime spokesman, Eric Fehrnstrom, said it was simply a policy fight: "We’re having an argument about welfare reform," he said, noting that Obama's administration had chosen to offer the waivers, and that the Administration had overstated the roles of Republican governors in seeking alternatives to the work requirement.

The election, Fehrnstrom said, "will be a referendum on the president's handling of the economy."