
Moore called the Chamber's help "significant" to the campaign and said he was "not worried about the broader discussion between the president, the vice president and the Chamber."
That "discussion" has turned into an all-out war being waged by top Democrats who are raising questions about whether the Chamber is funding its electioneering efforts with foreign money. Democrats have called on the group -- and other third-party organizations that are investing heavily in the 2010 cycle -- to disclose their donor lists.
2010 Election Maps: Follow the Senate, House and Governors' Races
The Chamber has repeatedly denied that any foreign funds are being used for its political activities.
"We are seeing an attempt to demonize specific groups and distract Americans from a failed economic agenda," Bruce Josten, the Chamber's executive vice president of government affairs said in a statement. "The Chamber will stay focused on representing and advocating our agenda of economic growth and speaking out against policies that are counter to those objectives."
The pushback has not stopped prominent Democrats, like Vice President Joe Biden, from keeping the issue front and center.
"Republicans used to be for transparency," the vice president told ABC News' Terry Moran on Tuesday.
"I'm not taking their word for it," Biden said of the Chamber's assertion that foreign money was not paying for political advertising.
Last week the left-leaning group MoveOn.org called on the Democrats who have received the Chamber's help to condemn the ads and ask that the television spots be taken down.
Maryland Rep. Frank Kratovil, a Democrat who is in a tight race with Republican State Sen. Andrew Harris in the state's 1st Congressional District, has no plans to renounce the Chamber, a campaign spokeswoman said on Tuesday.
2010 Elections: Maryland Races
"At the end of the day it shows that Frank is an independent leader," Kratovil's campaign manager Jessica Klonsky said of the ad. Kratovil's campaign website prominently touts his Chamber of Commerce endorsement.