The National Labor Relations Board has shot down, for the second time, Amazon’s attempt to derail a unionization vote by workers at its warehouse in Bessemer, Alabama. CNBC reports that the board on Friday rejected an appeal by Amazon, which was trying to stop mail-in balloting—even after successful mail-in voting in the presidential election. The ruling means that some 6,000 Amazon employees will begin sending in their votes on Monday, with counting to commence at the end of March. The last time Amazon faced a significant union push was in 2014 when workers in Delaware tried but failed to form a union. However, as CNBC notes, organizing efforts have gained steam over the last year—and Amazon is pushing back hard, even hiring the same law firm that helped it beat back the Delaware effort.