At the Democratic National Convention on Tuesday, Jason Carter said that his grandfather, former President Jimmy Carter, "can't wait to vote for Kamala Harris."

"Paw paw is holding on," Jason Carter said of his grandfather, who is 99 and has been in home hospice care for more than a year. "He is hopeful. And though his body may be weak tonight, his spirit is as strong as ever."

Carter turns 100 on Oct. 1, and early voting in his home state of Georgia begins two weeks later on Oct. 15.

He intends to vote by mail, his grandson said. And in Georgia, even if he reaches the end of his life before Election Day, that vote will still count.

In just two weeks, some states will begin mailing ballots to voters ahead of the November election. With the surge of early and mail-in voting over the last few decades, there have been circumstances where voters cast a ballot but die before Election Day.   

Wendy Underhill, Director of Elections and Redistricting for the National Conference of State Legislatures, said different states handle the situation in drastically different ways.   

“They can choose to accept them. They can choose to reject them. Or states can be silent on this question,” she said.  

In all, Spectrum News found at least 29 states where those votes would count. Nine states have laws that explicitly accept ballots from people who vote early, but die before Election Day. Another 20 state election offices, including New York, Ohio, and Texas, told Spectrum News they don’t have a law on the books, but would accept the votes.

On the other hand, 10 states, including Wisconsin, have laws that ban those ballots from being accepted. Five states, including North Carolina and Kentucky, don’t have a law on the books, but say they would not accept the ballots.

Three other states, including South Carolina, say it depends on the situation.  

“Both policies can be fully explained and rational, but each state gets to make its own decision on whether it says yes, that's a valid vote or no these are for only votes that are from folks who are with us on Election Day,” Underhill said.  

According to the most recent census, the five states with the most people over the age of 65 are Maine, Florida, Vermont, West Virginia, and Montana. All five of these states count ballots from people who vote early and die before election day.  

Bernard Fraga, Associate Professor of Political Science at Emory University, points out that it can be difficult for states to identify when a voter has died in this window.  

“In those states where there's verification process that happens well before election day, it would be kind of difficult to say, well, we're going to do a second round of checking just to make sure that nobody died,” he said.  

To find this information, some election offices get records from their state’s health department or the Social Security Administration. Others check local obituaries, or wait to hear from family members of the deceased.  

Another complicating factor is that different states remove mail-in ballots from their envelopes at different times.  

“At that point it's no longer attached to that voter,” Underhill said. “You can only get them back out if they're still in their envelope, and you can only pull that envelope back if you have evidence that the person has died.”  

It’s difficult to estimate how many people vote early and then die before election day. Fraga said dead voters are not likely to sway elections.    

“When we think about the broader scope of our democracy and instances where individual voters can make a difference, it's really those people who don't even try to cast a ballot that are impacting election outcomes,” he said.

He said states can do more to make people aware of their eligibility to vote.

To find out if you’re eligible to vote, go to USA.gov.