Organizers of an effort to repeal a Maryland law granting college tuition breaks to illegal immigrants appear to have met an initial threshold for collecting enough valid voters signatures to force the issue to a statewide vote.

An ongoing tally posted on the State Board of Elections Web site Tuesday morning showed 21,919 signatures have been validated, exceeding the 18,579 that were needed by the end of May for the petition drive to continue.

Opponents of the new law have until June 30 to collect a total of 55,736 valid signatures — or 3 percent of the number of votes cast in the last gubernatorial election. If they succeed, the new law will be put on hold and a statewide referendum will be held on the issue in November 2012.

More than 30,000 signatures submitted by the group from the first batch remain to be inspected by local election officials. So far, about 85 percent of the signatures that were submitted have been accepted. State election officials said they will continue to post updates as counting continues.

The law, signed last month by Gov. Martin O’Malley (D), would allow students who are illegal immigrants to pay the lower in-state rates at the state’s colleges and universities. To be eligible, students must have attended a Maryland high school for three years, provide proof that their parents are taxpayers and express their intent to become a citizen.