Joe Biden will be one formal step closer to the presidency after Tuesday’s deadline for states to certify their slates of electors to the Electoral College — locking in the names of the people who will formally vote to make Biden the president.

Once that happens, there’s little turning back. Congress must by law accept those electors if there’s no outstanding litigation, and President Donald Trump’s legal challenges have even less hope of changing the outcome. Electors meet in each state on Dec. 14 to officially cast their votes…

Federal law says that if a state appoints its electors and all litigation is resolved by Dec. 8 — the so-called safe harbor deadline — Congress must consider them “conclusive” when it meets in a joint session on Jan. 6 to tally the votes.

Normally, the deadline passes without much notice. But this year, Trump has refused to concede despite Biden’s clear victory with 306 Electoral College votes, the same as Trump had in 2016. Trump and his allies have claimed, without evidence, that the election was “rigged” and that he actually won.