Opponents of granting in-state tuition to illegal immigrants, who are trying to bring the issue to referendum, said they submitted 62,496 signatures on petitions late Tuesday night, far higher than their estimates.

Del. Neil Parrott, the Washington County Republican who is leading the drive, said the state election officials told them to count all the signatures, even the ones they thought would not be valid. Parrott estimates that 48,000 of the submitted signatures were valid, and they needed 18,500 by Tuesday.

“I was very pleasantly surprised at that number,” Parrott said. “People are flocking to sign this petition.”

By June 30, the group needs a total of 55,736 valid signatures to hold up implementation of the law and put it on the November 2012 ballot.

Parrott did not have a breakdown by county, but based on people who had filled out the petitions on the website MdPetitions.com, about 60% are Republicans, 25% are Democrats and 15% are unaffiliated.

—Len Lazarick