WASHINGTON — The GOP-controlled House and the Democratic Senate remain at loggerheads over debt legislation required to avoid a first-ever default on U.S. financial obligations as lawmakers and the White House head into a pressure-packed weekend in search of compromise.

A week of extraordinary partisanship was capped by a power play by Senate Democrats, who killed a House-passed debt limit increase and budget-cutting bill Friday night less than two hours after it squeaked through the House.

Senate Majority Leader Harry Reid, D-Nev., set up a test vote for the wee hours of Sunday morning to break a GOP filibuster.

However, before then the House was set to even the score by voting Saturday to reject an alternative measure by Reid even before the Senate has taken it up.

Democrats, Republicans and the White House, meanwhile, are expected to be deep in conversation in hopes of a potential compromise. Senate GOP leader Mitch McConnell of Kentucky is likely to play a pivotal role.