The financial industry is finding that winning in Washington comes at a cost.

Wall Street lobbied aggressively and succeeded late last year in persuading lawmakers to roll back rules for the US$700 trillion derivatives market. Instead of generating momentum for further changes to the Dodd-Frank Act, the victory sparked a populist uprising among Democrats that's had wide-ranging consequences, including stymieing less controversial requests from regional banks like Capital One Financial Corp.

"A short while ago there was bipartisan agreement on a number of common-sense improvements," said Rob Nichols, president of the Financial Services Forum that represents the chief executives of Wall Street's biggest banks. "Unfortunately, that bipartisan agreement is gone."