Senate leaders reached agreement on a bipartisan housing bill Wednesday, but will still have to deal with contentious amendments to extend President Bush’s tax cuts and change bankruptcy laws as early as Thursday.

The $12 billion, 10-year bill — which is not offset by spending cuts and has yet to be agreed to by the House — was announced by Majority Leader Harry Reid (D-Nev.) on the chamber floor, after a full day of horse-trading between Democrats and Republicans.

In the end, negotiators put the deal together simply by leaving out the biggest sticking points until later.

A Democratic proposal to allow bankruptcy judges to revise mortgage terms for primary residences won’t be in the bill, for example, and neither will a Republican attempt to extend President Bush’s 2001 and 2003 tax cuts. Instead, senators said those ideas will be able to be offered during an open amendment process starting as early as Thursday.

“Getting to this point has required compromise by all sides,” Reid said in a joint statement with Minority Leader Mitch McConnell (R-Ky.). “We hope to quickly come to a consensus to move this bill to the floor, consider amendments to it, and pass strong legislation that helps struggling homeowners and our economy as a whole.”

Democrats and Republicans are still negotiating over how to handle various amendments, and Majority Whip Dick Durbin (D-Ill.) said different amendments will face different vote thresholds for approval. Some will need only a simple majority to be added to the bill, while others will need the 60-vote margin necessary to overcome Senate rules extending debate.

Durbin said he is pushing for a simple majority margin for his bankruptcy provisions but is unsure of success.

The details of the bill, crafted by Sens. Chris. Dodd (D-Conn.) and Richard Shelby (R-Ala.), their parties’ respective leaders on the Senate Banking Committee, include $100 million for credit counseling, which both sides had called for, as well as $10 billion in extra bond authority for mortgage revenue bonds to refinance sub-prime loans.

Republicans won inclusion of a “carryback” provision allowing companies to report losses over a four-year period instead of two, which could lower the taxes owed by businesses.

Democrats also won about $4 billion in Community Development Block Grant (CDBG) funds, which Dodd had argued was necessary to help communities deal with the effects of foreclosed properties.

Both parties were already coalescing around some of the ideas, such as a proposal by Sen. Johnny Isakson (R-Ga.) for a $15,000 tax credit over three years for new or foreclosed homes. The revised proposal will allow homeowners to claim a non-refundable tax credit for $3,500 a year, for two years.

On another central question — loan limits to the Federal Housing Administration’s mortgage insurance program — senators are poised to settle at a $550,000 loan limit and keep the existing 3.5 percent down-payment requirement. Congress had already increased the limits from $360,000 in January, but Shelby had objected to the fact that under special provisions, loan limits in distressed housing areas were exceeding $700,000 in some cases.

“It only helps a small amount of people,” Shelby said of his opposition to the higher limit.

Much on the housing bill is still unclear, including the White House’s amenability to some provisions of the deal. The Bush administration is opposed to increased spending, for example, such as the CDBG money in particular.