The disagreement stems from a battle for leverage. Democrats want to strike an agreement now, when their political capital is at a high point following the election. They feel their position is further strengthened by the pending expiration of the Bush tax cuts and scheduled cuts to defense spending.

Republicans say a broad package would be too complex to finish in the next six weeks. But waiting until next year to complete an agreement would also help them politically as President Obama’s election mandate is likely to fade…

Democrats told Boehner they would not accept any postponement of a debt deal unless Republicans agreed to a substantial down payment, and pushed for the up-front funds to come from raising tax rates on the highest two income brackets, according to a Democratic aide familiar with the meeting.

By pressing for significant progress on a deficit-reduction deal during the lame duck, Democrats are hoping to push Republicans to accept hefty tax hikes before the new year.