WASHINGTON (AP) — Senate Republicans are poised to use a filibuster to derail Democrats’ effort to launch a bipartisan probe of the Jan. 6 attack on the Capitol. The showdown will be the first time this year the GOP has used the delaying tactic to try killing major legislation. The GOP seemed certain to succeed, but their victory may prod Democrats closer to curbing or eliminating a legislative tactic that’s been the bane of Senate majorities since the Founding Fathers. Progressives hope that if the commission bill dies by filibuster, the defeat would pressure Democrats to finally get rid of the tactic.