HOUSTON -- Note: The following story is a verbatim transcript of an Investigators story that aired on Thursday, Oct. 8, 2008, on KPRC Local 2 at 10 p.m. Local 2 investigates dead voters. More than 1.9 million people are registered to vote in Harris County alone. But how many of the people listed on the voter roll are actually eligible to cast a ballot? Investigative reporter Amy Davis shows you how hundreds of voters could sway this year's election -- voters who are not even alive. "All-in-all, a great person, a great woman, just a wonderful person" is how Alexis Guidry described her mother to Local 2 Investigates. "As far back as I can remember, they've always voted in the election," Guidry said of her parents. The March 2008 Primary was no exception. Voting records show Alexis' mom, Gloria Guidry, cast her ballot in person near her South Houston home. "It was just very shocking, a little unsettling," said Alexis Guidry. It's unsettling because Gloria Guidry died of cancer 10 months before the March Primary. "She'd be very upset," Guidry said when asked what her mom would think. Trent Seibert, of Texas Watchdog, says you should be too. "This is really disquieting. It's concerning. It's worrisome," said Seibert. He heads up the non-partisan news group on the web. Texas Watchdog compared Harris County's voter registration roll with the Social Security death index and found more than 4,000 matches -- registered voters that, it appears, are already dead. Some of them, like Henderson Hill's late wife Linda, voted postmortem. "I would like to know who did it, myself," Hill told Davis. We don't know who used Linda Hill's or Gloria Guidry's IDs to vote, but we do know if their names had been purged from voter rolls after they died, using their IDs wouldn't have worked. "This is a red flag. No matter where you are, this should set off alarm bells," Seibert said. "Someone needs to take a look at this." Local 2 Investigates took the information to the Harris County Voter Registrar. "We just kind of work with the systems that we're allowed to," explained George Hammerlein, the director of Harris County Voter Registration. The county's system for culling deceased voters from the roll seems painfully primitive. We watched employees clip obituaries from the newspaper and sort through probate records for names matching those on the roll. But, Hammerlein says while fraud is a concern, for his office, disenfranchising voters is a bigger one. "We do all we can, but you know we'd rather err on the side of leaving people on the roll instead of taking them off inadvertently," he said. But could that cautious "better safe than sorry" standard sway an election some say will be a close one? Texas Watchdog found 4,462 registered voters who appear to be deceased. In 2000, George Bush won the presidential election by a mere 537 votes in Florida. "We've never had any evidence there's a concerted attempt at fraud," Hammerlein told Local 2. But there is evidence the state agency in charge of ensuring only eligible voters can vote is not. The State Auditor's Office conducted an audit of the voter registration system at the Secretary of State's Office last November. Auditors identified 49,049 registered voters state-wide who may have been ineligible to vote. Approximately 23,576 may have been deceased and another 23,114 were possible felons. And they found more than 2,359 duplicate records. The auditor did not find any instances in which potentially ineligible voters actually voted, but they wrote, "Although the Secretary of State's office has processes to identify many ineligible voters and remove them from the State's voter registration list, improvements can be made." Almost a year after this audit, we wanted to know if the Secretary of State has made any improvements. Have they added any safeguards to the process? No one from that office would talk to us on camera, but the Director of Elections told us, "We'd rather err in leaving someone on the roll than taking someone off." "If there's something wrong here, if there's something amiss, this is the worst election to have that happen, "Seibert warned. And Guidry agrees. "I don't think it's a matter that she would take lightly," she said of her mom. In what she calls an historic election, Guidry says her mother wouldn't want anyone speaking for her. "I think she would definitely do all that she could just to make sure things were on the up and up." We sent the information we showed you to the Director of Elections in Austin. She said her office refers any credible allegation of election fraud to the Attorney General for investigation. She said the cases we presented would be felony violations.