NEWT Gingrich's portrayal of Mitt Romney as the candidate of Wall Street money was underscored by the latest political donor records, which revealed the top four contributors to a political action committee (PAC) allied to Romney were hedge fund managers.
All up, almost 60 corporations and wealthy individuals donated at least $US100,000 ($A94,000) each to the Romney PAC "Restore Our Future", which raised more than $US20 million in the second half of 2011.
A $US10 million donation from casino mogul Sheldon Adelson and his wife, Miriam, to "Winning Our Future", a committee backing Mr Gingrich, did not feature in the latest accounts because it was given in January.
About half of the $US2 million raised by the group in December came from associates of the Adelsons.
Mr Adelson, a staunch advocate for Israel, was rewarded in Mr Gingrich's speech in Florida with a renewed promise that, if elected, he would relocate the US embassy in Israel to Jerusalem, from Tel Aviv, a move long supported by Mr Adelson.
Of other key activists, "American Crossroads", the Republican group backed by former George W. Bush adviser Karl Rove, said it had raised $US51 million along with its non-profit arm last year. Most of its $US11 million in contributions over the past three months came from roughly a dozen donors.
Once, strict rules governed how much could be donated to PACs. Corporate and union money was banned from PACs, while direct donations to candidates were capped at $US2500.
However, a 2010 Supreme Court ruling paved the way for uncapped donations to PACs by affirming the right to free speech and political advocacy.