Obama's Non-Grassroots Fundraising

Instapundit reports:

"As in other recent campaigns, lawyers account for the biggest chunk of Democratic donations." Nobody's more grassrootsy than us lawyers! We're the salt of the Earth. But it's not just lawyers: "When you break it out by individual companies, you find that employees of Goldman Sachs gave more to Obama than workers of any other employer. The Goldman Sachs geniuses are followed by employees of the University of California, UBS, JPMorgan Chase, Citigroup, National Amusements, Lehman Brothers, Harvard and Google."

Are these groups trying to buy the election?