CNN reports that 70% of Republicans do not believe Biden won the election.

[Buckeye_Democrat]

26. Democrats weren't in that much denial in 2016!

And that's with Clinton winning the popular vote!

One-third of Clinton supporters say Trump election is not legitimate, poll finds
https://www.washingtonpost.com/news/the-fix/wp/2016/11/13/one-third-of-clinton-supporters-say-trump-election-is-not-legitimate-poll-finds/
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There are sharp racial and gender differences in Clinton supporters’ acceptance of the results. Only 18 percent of whites who supported Clinton say Trump is not the legitimate winner, identical to the public overall, but fully 51 percent of black, Hispanic and other nonwhite Clinton supporters say Trump’s victory was illegitimate. Women who supported Clinton are twice as likely as men to question the legitimacy of Trump’s victory, 42 vs. 21 percent...

In the Post-ABC poll, nearly all of Trump’s supporters say he was elected legitimately, 99 percent, also marking a turnabout in confidence from one week ago when only 69 percent said they were prepared to accept the results of the election.
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Edit: The anti-democratic attitudes of Trump supporters, and their lack of shame about it, really came through with the part that I put in bold!
So what if a Democrat received 75% of the vote someday?!
"Sorry! Our guy won the electoral college and it's totally legitimate! You lost fair and square!"
Such a-holes!