Christopher Dodd, chairman of the Senate banking committee, is poised to introduce legislation today that would likely be harder on financial firms than previously expected. The Obama administration has pushed for tougher regulation as it sees a political advantage in zeroing in on Wall Street. The Federal Reserve appears to be the biggest winner in Dodd's proposal. The central bank would supervise areas of the economy that are unregulated. Dodd is striving to hold votes on the legislation as early as next week.