The U.S. Senate has opened debate on the most sweeping package of financial reforms since the Great Depression of the 1930's.   

The excesses of Wall Street contributed to an economic recession that spread quickly through America and around the world last year.

The goal in the U.S. Congress is to prevent this kind of financial meltdown from ever happening again.

After days of parliamentary delays, the Senate finally took up legislation designed to regulate Wall Street and protect consumers.

Connecticut Democrat Christopher Dodd - the chairman of the Senate Banking Committee - was the first to speak.

"I want to begin the debate with a message to those who have seen the acrimony in this chamber over the last couple weeks who have concluded that this Senate is not up to getting the job done on a piece of legislation of this import [importance] and this size," said Senator Dodd.

Dodd said this would not be a repeat of health care reform, which passed without a single Republican vote.  He said this time, Democrats and Republicans will find common ground.

But Senator Richard Shelby of Alabama - the top Republican on the banking panel - warned there are deep differences.

"This bill will help the big banks get bigger as it is written today, and further tilt the competitive playing field against small and less  politically connected firms," said Senator Shelby.

As the debate got underway, Treasury Secretary Timothy Geithner made the case for reform before a Senate committee.

"Over the past few weeks, opponents of reform have tried to convince the American people that these reforms will hurt Main Street or help Wall Street," said Secretary Geithner. "Those arguments won't work because they aren't true."

The measure before the Senate is lengthy and complex, and the debate on the bill could take weeks.

Economist Martin Neil Bailly is with the Brookings Institution in Washington.  He says the reforms may be effective, but warns another financial crisis is still possible.

"I think if we improve the quality of regulation, improve the structure of regulation, if we have a regulator, a systemic monitor to make sure that we look across the system and indeed across the globe then I think we can minimize the chances of another crisis," said Neil Bailly. "I don't think we can give any guarantees."

The House of Representatives passed its version of financial reform legislation late last year.  Any differences with the bill that ultimately clears the Senate must be reconciled before the measure can be signed into law by the president.