WASHINGTON — Ending a postelection detente, Senate leaders shredded each other Tuesday in increas­ingly bitter terms over a Democratic proposal to dramatically overhaul the chamber’s long-standing rules on filibusters.

The back-and-forth left the Senate in a partisan standoff that is ill suited for the bipartisan talks expected over the next four weeks to reach a compromise that would avert more than $500 billion in annual auto­matic tax hikes and spending cuts that are set to kick in after New Year’s Day.