New Mexico's top elections official told lawmakers Tuesday that she is concerned a review of the state's voter-registration rolls and a list of the thousands of foreign nationals who have been issued driver's licenses under a much debated state law has turned up evidence of fraud.

Secretary of State Dianna Duran's office has spent two days cross-checking the databases. She testified during a hearing on a voter-identification proposal that the work is far from over, but that her office has found some instances in which people without valid Social Security numbers cast votes in past elections.

Duran said she expects the review to be complete later this week.

"It's very concerning to the secretary. We feel it affects the integrity of elections," said Bobbi Shearer, the director of the state Bureau of Elections.

Immigrant- and voter-rights groups have questioned the validity of the review, but a spokesman for Gov. Susana Martinez said the initial report from the Secretary of State's Office should be a concern for New Mexicans.

"Each and every illegally cast vote disenfranchises a New Mexican, and this is yet another reason why the governor strongly supports repealing the law that gives driver's licenses to illegal immigrants," said spokesman Scott Darnell.

The issue of whether New Mexico should issue driver's licenses to foreign nationals, particularly illegal immigrants, has been the focus of much debate during the legislative session.

Under a 2003 law, more than 80,000 driver's licenses have gone to foreign nationals. The state says it doesn't know how many of those went to illegal immigrants because it doesn't ask the immigration status of license applicants.

Immigrant applicants for driver's licenses don't need a Social Security number as part of their identification. Instead, they can submit a taxpayer identification number issued by the federal government, along with other identification such as a passport and a Matricula Consular card issued by a Mexican consulate.

Two other states — Washington and Utah — also allow illegal immigrants to get licenses because their laws do not require proof of citizenship. However, Utah's driving permits cannot be used as a government identification card.

Shearer described the cross check as fairly difficult. The office is reviewing names, birth dates and Social Security numbers, and more queries are planned.

Of the suspicious instances, Shearer said: "There's evidence that they're in the foreign national database, that their name and date of birth matches, and their Social Security number in our database is not valid, and that they did cast votes."

Marcela Diaz of the immigrant-rights group Somos Un Pueblo Unido said the cross check won't help to identify illegal voting because she contends the list used by the Secretary of State's Office also includes U.S. citizens who did not use their Social Security numbers when obtaining a license and those residents who have since become naturalized.

"Basically it's an absurd way of trying to ferret out people who are illegally registering. There has been no evidence to show that immigrants who are either legally permanent residents or undocumented are trying to do it," Diaz said.

Most people in the immigrant community would not attempt to vote illegally because it would prevent them from one day becoming a legal permanent resident or citizen, Diaz said.

"That's not a risk people are willing to take," she said.

The executive director of Common Cause New Mexico requested Duran's office forward any evidence of illegal voting to law enforcement officials. "... in recent years, many allegations of election-related felonies have circulated in our state. Time after time, these allegations have been proven to be fictitious," the group's executive director Steve Allen said in a news release. "Sadly, the same pattern has repeated itself over and over again. At this point, the evidence should be forwarded to law enforcement before, or at least at the same time as, such allegations are circulated to the media. We don't need more senseless panic about a problem that time and time again has proven to be largely imaginary."

The Secretary of State's Office also is awaiting more data from the Motor Vehicle Division in response to a 2006 lawsuit filed by the state Republican Party that sought to disclose the names of illegal immigrants who had obtained driver's licenses.

The party wanted the names — along with other information withheld by former Democratic Gov. Bill Richardson's administration — so it could check them against the voter rolls. Republicans were concerned that immigrants could use their driver's licenses to register to vote.

As part of an agreement to settle the claim, the Motor Vehicle Division is gathering information on foreign national license holders as of July 2006.

Darnell said the agreement ensures federal and state privacy laws are upheld by having the Secretary of State's Office check the names against the voter rolls, rather than releasing the information to the Republican Party.

Whether the rest of the information, some of which pertains to an audit of foreign national license holders, is released depends on the New Mexico Supreme Court. The court heard arguments Monday but has yet to issue a ruling.

Steve Terrell contributed to this report.