EDITOR'S NOTE: Watch the video above for step-by-step instructions on how to properly fill out and return your mail-in ballot in Pennsylvania.
The potential pitfalls abound for Pennsylvania voters who will be using mail-in ballots in the Nov. 3 election.
First, it was concerns about the U.S. Postal Service's ability to handle millions of ballots being sent to and from county offices in October and early November.
Now, it's the secrecy envelope in which the completed ballot is stored that has election officials worried about having to throw out otherwise qualified votes.
Mail-in ballots are still new to many of the millions of Pennsylvanians signing up to use them in the Nov. 3 presidential election. But every vote will be crucial in the race between President Donald Trump and former Vice President Joe Biden. Trump won the state and its 20 Electoral College votes by just 44,000 votes in 2016 -- less than 1% of the six million ballots cast.
Mail-In Voting: What to Know
Here is a checklist of what you need to do in order to make sure your mail-in ballot is certified and counted in November.
Register to vote by Oct. 19
If you have not registered to vote yet, now is the time! And if you would like to vote by mail, the earlier you get the process going the better. Here is a link to the state's voter registration page.
Apply for a mail-in ballot ASAP, if you don't want to vote in person
The deadline to apply for a mail-in ballot is Oct. 27, but you can't wait till then. The consensus among election experts is that anyone who asks for a mail-in ballot that close to Nov. 3 will not be able to get it, fill it out and send it back in by Election Day.
Check off the box for receiving email alerts
When applying for the mail-in ballot, there is an option for voters to have email updates sent. These alerts are valuable for knowing the status of your ballot: when it is en route to you, when your county election office has received it from you, when your vote has been counted. It is definitely worth providing an email for these alerts.
Carefully open the ballot package when you receive it in the mail
A good rule of thumb for voters who have requested a mail-in ballot is to take better care when opening your mail. One of the most common problems that voters faced in the June primary was ripping their ballots or the envelopes that come with the ballots in half, according to one election official. He said it appears that many voters initially believe the ballot or some of the contents with the ballot were junk mail. So take care when sorting your mail, and when opening the ballot package, make sure not to throw out any of the contents. There is more to this than you think!
Make sure there is a secrecy envelope included
One of the pieces of content included in the ballot package you'll receive is a secrecy envelope. The mail-in ballot must be inside this envelope when county election boards receive it back from a voter. PLEASE NOTE: A mail-in ballot NOT in a secrecy envelope, also known as a "naked ballot," will NOT BE COUNTED!
Fill out the ballot immediately, put it in the secrecy envelope, then put it in the outer return envelope
Don't wait to fill out the ballot after you get it. Take care of business. Don't put it off. But there is one more crucial step before putting it in the mail or a county election drop box. And that is...
Don't forget to sign the outer envelope before sending it back!
A signature is required on the back of the outer envelope that contains the secrecy envelope and ballot. Make sure to sign the back of that envelope before putting it in the mail or a county drop box. A mail-in ballot that arrives without that signature will be thrown out.
Counties across the state will be installing drop boxes for voters who want to return mail-in ballots without using the U.S. Postal Service. (NBC10 will soon have a graphic that shows locations of drop boxes.)
In the state's June primary, more than 1.5 million voters cast ballots using mail-in voting, which was allowed for the first time ever. Previously, a much smaller percent of voters were allowed to cast ballots that way using the absentee method. Officials now expect as many as 3 million voters to using mail-in voting in the general election.
That's why election officials and voter advocates are warning voters who will use mail-in ballots to make sure they do it right. Every vote counts, until it doesn't because you didn't sign in the right spot or seal the right envelope.
Mail-in ballots were certified by the Pennsylvania Department of State on Sept. 17, and county officials said they immediately began printing ballots to send to voters. The first ballots should arrive in voters' mailboxes in the last week of September.