"A year has passed and nothing has been done," Clinton said. "Fifty million Americans, from New York to Michigan were affected by this blackout, and the president and his allies in Congress have blocked all efforts to address the issue."

On Aug. 14, 2003, a power line in Ohio drooped into a tree, triggering a blackout that rapidly blanketed most of New York, Ontario, eastern Michigan and northern Ohio, and parts of Pennsylvania, New Jersey, Connecticut and Vermont. The blackout left an estimated 50 million people without power, costing the U.S. economy between $4 billion and $10 billion, according to the U.S.- Canada Power System Outage Task Force, created by President Bush and former Canadian Prime Minister Jean Chretien to investigate the blackout.

The task force blamed the blackout on mistakes and conditions that caused a cascading surge of power to sweep through the complex electric grid, prompting transmission lines and generators to shut down. Utility companies have voluntary reliability standards to prevent such blackouts, but federal regulators have no power to enforce the rules.

Clinton and Sen. Maria Cantwell, D-Wash., have proposed legislation that would create mandatory reliability standards for electric utilities.

The legislation would give the Federal Energy Regulatory Commission the authority to devise a system of mandatory and enforceable standards for operation of the nation's power grid.

Republican leaders in Congress want the mandatory regulations to be included in a larger, controversial overall energy bill. But that legislation has stalled in the Senate.