As noted below, the Democrats' fumfer about outside money is ludicrous on its face, given the help they get from their union allies and the corporate money that helped Obama two years ago. Another avenue of attack is their claim that the GOP is being helped by foreign money, mainly on the theory that outside corporate groups get money from US subsidiaries of foreign companies - but it turns out that 49 of the 59 Democratic Senators have taken PAC money from subsidiaries of foreign companies. Three Senators now up for re-election - Barbara Boxer, Patty Murray and Kirsten Gillibrand - have each accepted over $100,000 from subdiaries of foreign companies. In Illinois, Alexi Giannoulias accused Mark Kirk of "economic treason" over a fundraiser in China...but went and held his own fundraiser in Canada. (And this is on top of the fact that the Obama campaign in 2008 deliberately removed safeguards against accepting donations by credit card from foreign nationals.)
So much for that argument.