HOUSTON -- Scanning voter registration cards is one of the first steps in making sure citizens will be registered to vote the upcoming presidential election, KPRC Local 2 reported Saturday.

But just because a resident mailed in their card in on time doesn't mean early voting will be problem-free.

The Secretary of State's Office in Austin must also verify the applications, using driver's license and partial Social Security numbers before voters are added to lists in each county of qualified voters.

"Right now we've got 21,000 people on the rolls, but we have to wait to have them tell us it's OK. Part of the problem is clearly that they're behind on their matches with the Social Security Administration, so there are people who will simply have to wait," said Paul Bettencourt, Harris County Tax Assessor Collector.

According to Bettencourt, Harris County also received a record number of voter registration applications -- more than 97,000.

His office is working through the weekend to make sure they get as many of those people on the roll before the start of early voting, which begins Monday.

"If you're worried that you still haven't gotten your voter registration card, you can check your status at www.hcvoter.net and you'll see if your card is there. But you can just bring your driver's license and you're good to go," said Bettencourt.

The Harris County Clerk also added there will be 36 voting locations open from Oct. 20 to Oct. 31 in Harris County.

This year, voters can help expedite the check-in process at the poll if they choose to use their driver's license or Texas ID to identify themselves during the early voting period.