Outcome of the 2020 U.S. presidential election

• Joe Biden won the 2020 U.S. presidential election, receiving 306 electoral votes to Donald Trump’s 232, and winning the national popular vote by over 7 million votes.

Pennsylvania and Philadelphia mail-in vote dynamics

• Pennsylvania, including Philadelphia, counted many mail-in ballots after election night because state law did not allow processing of mail ballots far in advance. These late-counted mail-in votes were heavily pro-Biden and eroded, then overturned, Trump’s initial election-night lead in the state, which was widely discussed as the “blue shift” from mail-in ballots. (Multiple authoritative election-postmortem analyses describe that Biden’s eventual Pennsylvania win came as large, strongly Democratic mail-in batches from cities like Philadelphia were reported in the days following November 3, 2020.)

Comparison to the prediction

• Chamath’s normalized prediction: that Biden would win the 2020 election, and that this expectation rested on a strongly pro-Biden mail-in vote from Philadelphia being counted after election night.
• What happened: Biden did win the presidency, and Pennsylvania’s late-counted, urban mail-in ballots (including those from Philadelphia) played a crucial role in overcoming Trump’s early lead and securing Biden’s statewide victory, which in turn was pivotal to his overall Electoral College majority.

Because both the core outcome (Biden winning) and the described mechanism/timing (crucial, strongly pro-Biden Philadelphia/mail-in vote counted after election night) match what actually occurred, this prediction is right.