WASHINGTON — A mortgage rescue plan to save hundreds of thousands of homeowners from foreclosure drew overwhelming Senate support yesterday, inching toward passage despite Republican objections.

The Senate voted 76-10 to advance the bill, a broad array of housing measures including overhauls of the Federal Housing Administration, the Depression-era mortgage insurer, and government-sponsored home loan giants Fannie Mae and Freddie Mac.

Its centerpiece is a new $300 billion FHA program to allow debt-ridden homeowners who are currently too financially risky to qualify for government-backed loans to refinance into safer, more affordable mortgages.

The measure is on track for passage by an overwhelming margin, possibly by week’s end. It has survived several test votes in the Senate, repeatedly demonstrating that there’s enough support for it to override President Bush’s promised veto.

But Senator Ensign, a Republican from Nevada, is blocking its progress because Democratic leaders have refused to allow a vote on attaching an $8 billion package of renewable energy tax breaks. Mr. Ensign has said he wants the tax incentives to hitch a ride on the housing measure because it has a good chance of being signed into law by Mr. Bush.

“This will be the major achievement and accomplishment of this Congress when it comes to dealing with the underlying economic crisis, which is at its heart the foreclosure crisis,” Senator Dodd, a Democrat from Connecticut and the chairman of the Banking Committee who wrote the legislation.

Beyond the Senate, the election-year package still faces a tricky path.

The president has said he thinks a deal is possible, but the White House is balking at key portions of the bill, particularly $3.9 billion included for buying and fixing up foreclosed properties. Democrats argue the money is key to preventing neighborhood blight, but most Republicans call it a bailout for lenders who helped cause the mortgage mess.