The Republican plan to block debate on Senate Bill 649, which requires background checks on almost all gun purchases and transfers, failed spectacularly Thursday morning when sixteen Republican Senators joined almost all of the Democrats to vote in favor opening debate on the bill. Among those voting to defeat the filibuster were 9 Democrats with “A” ratings from the National Rifle Association, and 12 A-rated Republicans (out of 16 Republican “ayes”). Two Democrats, Sen. Mark Pryor (D-AR) and Sen. Mark Begich (D-AK), joined the majority of Republican Senators who tried to prevent debate, much less a vote, on the bill....