Voting experts and elections officials aren't worried about significant voting fraud from the increased use of mail-in ballots this pandemic-hit election, but user error is a real concern. And it's a growing concern in Pennsylvania, a key swing state, after the state Supreme Court ruled last week that mail-in ballots received without a second "secrecy envelope" inside will be thrown out.

They're called 'naked ballots'. Tonight, there's concern they could disenfranchise 100,000 Pennsylvania voters. In 2016, the state was decided by 44,000 votes. Key reminder: Ballot goes into secrecy envelope, both go into outer, declaration envelope.https://t.co/cPLTbu2tWd pic.twitter.com/Zk5jNbFAsb — David Kaplan (@DKaplanWTAE) September 22, 2020

The disqualification of these "naked ballots" will "cause electoral chaos, leading to tens of thousands of discarded votes" and "significant post-election legal controversy, the likes of which we have not seen since Florida in 2000," Philadelphia's top elections officials warned Monday. President Trump won Pennsylvania by 44,000 votes in 2016, and the state is so important this year, FiveThirtyEight says, "our model gives Trump an 84 percent chance of winning the presidency if he carries the state — and it gives [Demorat Joe] Biden a 96 percent chance of winning if Pennsylvania goes blue."

The disqualification of 100,000 or more "naked ballots" could tip the election. But voters worried they might have left out the secrecy envelope can track their mail-in ballot via a state website, votesPA.com/MailBallotStatus, to make sure it is counted or take remedial steps. Using both envelopes is not an onerous step if you know to take it, and the Pennsylvania Secretary of State's office put out a short video to walk new (or experienced) mail-in voters through the steps (in English and Spanish).

Stephen Colbert also has some key dates for voting in Pennsylvania — and every other state — on a new website, BetterKnowABallot.com.

Colbert's video doesn't include the two-envelope rule, so it's not clear how well he really knows Pennsylvania's ballot. But his site has links to every state's election site, in case you need to learn how, where, and when to cast your one precious vote. Peter Weber