Amid widening criticism, Obama drops claim about foreign cash in the campaign

Are Democrats recalibrating their message on alleged foreign money in the 2010 elections?

Days after making it a key part of his stump speech, President Obama on Monday dropped mention of the claim he and other Democrats have lately lodged about the U.S. Chamber of Commerce allegedly funding attack ads with contributions from foreign companies. The claim, which was also echoed in a Democratic National Committee ad, has been debunked by several media organizations, including the New York Times.

On Monday, the nonpartisan Factcheck.org also slapped down the charge. Factcheck reporter Brooks Jackson wrote: "Accusing anybody of violating the law is a serious matter requiring serious evidence to back it up. So far Democrats have produced none."

White House officials had suggested over the weekend that they wouldn't back off the claim until they have proof that the chamber isn't using foreign contributions. Yet Obama made no mention of the foreign-money issue during a speech at a fundraiser Monday night in Miami. He also dropped lines attacking the GOP's use of outside money, which he had previously said was a "threat to democracy."

That could be a sign that Obama is ceding the attack-dog role to Vice President Joe Biden, who raised the issue several times at fundraisers Monday and again Tuesday in an interview that will air in a few hours on ABC's "Nightline." Asked about the chamber's claim that "not one cent" of foreign cash is being spent on the elections, Biden scoffed. "Show me," he told ABC's Terry Moran. "Republicans used to be for transparency. Show me. … I'm not taking their word for it."

Meanwhile, other Democratic and liberal groups are jumping on the attack bandwagon, as the Wall Street Journal's Elizabeth Williamson reports.

The nonprofit groups Public Citizen and Public Campaign along with the liberal activist group MoveOn.org (which has come under attack from Republicans for its election spending) are asking the Department of Justice and Internal Revenue Service to investigate the so-called shadow GOP groups and their spending. The groups say they will also press media outlets that run ads from the groups "to question whether the cash used for the ad buys is legal for that purpose."

(Photo of Obama and Biden on Sunday in Philadelphia: William Thomas Cain/Getty Images)