Democrat Joe Biden is winning the presidential popular vote by more than 3.9 million votes and is on his way to being the first candidate to defeat an incumbent president in 28 years and only the fourth in the last 100. He did so by flipping Arizona, Michigan and Wisconsin away from President Donald Trump , and likely Pennsylvania and perhaps even Georgia as well.

But approaching 48 hours since polls closed nationwide, Biden has not been declared the winner. This has opened a wide avenue for Trump to falsely claim the presidency is being stolen from him, which is in turn provoking angry supporters to turn out in increasing numbers outside vote-counting centers and in state capitols.

This is happening because Republican-controlled legislatures in Michigan, Pennsylvania and Wisconsin refused to update their laws to allow election officials to open, process and count mailed ballots early enough to get close to a complete tally on Election Day.

Biden has won Michigan by over 150,000 votes, Wisconsin by a slimmer 21,000 or so and he appears on pace to win Pennsylvania. These leads may grow as provisional ballots are counted. Had these three states been allowed to process and count mailed absentee ballots ahead of time, Biden would have hit 270 electoral votes on election night. Michigan and Wisconsin were not called for Biden until Wednesday afternoon, and there is not yet a projected result in Pennsylvania.

One likely motivation for that delay was to create a window for the Trump campaign to mount legal challenges to block counting of presumed Biden-heavy mailed votes. Trump is now down in too many states by, in many cases, too many votes, for that strategy to work. But its still created a dangerous vacuum for his claims of illegitimacy and fraud.

The coronavirus pandemic dramatically altered the way Americans voted. Far more used absentee ballots, as nearly every state liberalized their rules for this to allow everyone to cast one without an excuse. Like so much else in the country, how people decided to vote polarized along partisan lines. Democrats chose to cast absentee ballots in substantial numbers, while more Republicans chose to vote in-person on Election Day. This split created a skewed view of the results based entirely on when election officials were allowed to count mailed ballots.

Same day in-person votes went heavily for Trump, while the early returned absentee ballots, which constituted the vast majority of votes in strong Democratic counties, had to wait.