A proposal by top Democrats in the Senate regarding the tax credit for first-time homebuyers could come to a vote before expiring on November 30. In the proposal, the tax credit would be gradually phased out over the course of next year.

The proposal, by Majority Leader Harry Reid, D-Nev., and Senate Finance Committee Chairman Max Baucus, D-Mont., would extend the $8,000 tax credit through March 31.

The plan, which could face a vote in the Senate this week, appears to pre-empt a far more costly $17 billion bipartisan plan that would extend the $8,000 credit through June 30, 2010, boost the income cap for eligibility and open the credit to all buyers, rather than just first-timers.

Senators are planning to add the homebuyer tax credit extension to legislation to extend unemployment benefits by up to 20 weeks. That bill faces a key test vote on Tuesday.

The plan is especially popular with homebuilders who raked in huge amount of profits during the boom years but are struggling today. Critics of the proposal say it’s a steal as some of the very companies that helped build up the housing bubble years ago will benefit from this.