WASHINGTON – In a victory for Republicans, the federal government has agreed to let Florida use a law enforcement database to challenge people’s right to vote if they are suspected of not being U.S. citizens.

The agreement, made in a letter to Florida Gov. Rick Scott’s administration that was obtained by The Associated Press, grants the state access to a list of resident noncitizens maintained by the Department of Homeland Security. The Obama administration had denied Florida’s request for months, but relented after a judge ruled in the state’s favor in a related voter-purge matter.

Voting rights groups, while acknowledging that noncitizens have no right to vote, have expressed alarm about using such data for a purpose not originally intended: purging voter lists of ineligible people. They say voter purges less than four months before a presidential election might leave insufficient time to correct mistakes stemming from faulty data or other problems.

Democrats say that the government’s concession is less troubling than some GOP-controlled states’ push to require voters to show photo identification.

But Republicans count it as a victory nonetheless in their broad-based fight over voter eligibility, an issue that could play a big role in the White House race. That’s especially true in pivotal states such as Florida, Colorado, Nevada and North Carolina.

Republican officials in several states say they are trying to combat voter fraud. Democrats, however, note that proven cases of voter fraud are rare. They accuse Republicans of cynical efforts to suppress voting by people in lower socio-economic groups who tend to vote Democratic.

Colorado and other states have asked for similar access to the federal database being granted to Florida.

After a judge recently ruled against federal efforts to stop Florida’s aggressive voter-list review, the Homeland Security Department this past week agreed to work on details for how the state can access the federal SAVE database — Systematic Alien Verification for Entitlements — to challenge registered voters suspected of being noncitizens.

Florida has agreed that it can challenge voters only if the state provides a “unique identifier,” such as an “alien number,” for each person in question. Alien numbers generally are assigned to foreigners living in the country legally, often with visas or other permits such as green cards.

Unless they become naturalized citizens, however, these people cannot vote.

The agreement will prevent Florida from using only a name and birth date to seek federal data about a suspected noncitizen on voter rolls. It’s unlikely to catch illegal immigrants who might have managed to register to vote because such people typically would not have an alien number.

Scott, whose administration had sued Homeland Security for access to the SAVE list, said the agreement “marks a significant victory for Florida and for the integrity of our election system.”

“Access to the SAVE database will ensure that noncitizens do not vote in future Florida elections,” Scott said Saturday.

In a letter Monday, the department told Florida it was ready to work out details for providing access to the SAVE list. The letter was signed by Alejandro N. Mayorkas, director of U.S. Citizenship and Immigration Services.

It follows a flurry of legal actions between Florida and the federal government. On June 11, the Justice Department said it would sue Scott’s administration on grounds that the state’s voter-purge efforts violated voting rights laws.

The same day, Scott announced a lawsuit against Homeland Security seeking access to the SAVE list. He said it could be a valuable tool in determining who is a citizen. Two weeks later, a U.S. judge blocked the federal efforts to stop Florida’s voter review efforts; the Mayorkas letter soon followed.

A Homeland Security spokesman said Saturday the agency had no further comment.

Department officials told the Orlando Sentinel last month they had concerns about using the SAVE list for voter-review purposes. They said the list’s information is incomplete and does not provide comprehensive data on all eligible voters, the newspaper reported.

Scott’s administration hopes to restart a suspended voter registration purge that was hampered this year by faulty data and bad publicity. The review, based largely on driver’s license information, turned up 2,625 suspected noncitizens registered to vote.

But some were in fact citizens. An examination by the Tampa Bay Times found “just a handful” that had actually voted illegally. Florida officials said access to the federal data will allow a more reliable review of voter rolls.

While some noncitizens who are legal residents may knowingly try to register and vote, others apparently do so unwittingly. After obtaining a driver’s license, some assume they also can vote, officials say.