For two decades in Maryland, opponents of statewide measures as diverse as speed cameras and early voting have been mounting petition drives to repeal the laws. Those efforts have all failed.

Until now.

Last week, Del. Neil C. Parrott and others won a key victory in their campaign to repeal a new law allowing undocumented immigrants to pay in-state tuition rates at public colleges. Elections officials announced that the opponents had enough signatures to suspend the law and put it to a statewide vote next year.

Parrott’s effort relied, in part, on something his predecessors didn’t use: Internet software that ensured precision and allowed him to avoid the chance of signatures being rejected on legal technicalities.

Of course, Parrott (R-Washington) spent time at swim meets, carnivals and parades to help gather the tens of thousands of signatures that were needed. But about a third of the total number came from people who logged on to his Web site and clicked on a widget that made it easy for them to fill in their information correctly.

The system is simple. Thousands of voters, egged on by a media blitz on talk radio and Web sites and through targeted e-mail, found their way to They typed their names, birth dates, Zip codes and e-mail addresses into a basic form, just as if they were buying a sweater online. The software then tapped into voter-registration data to fill out the petition sheet in the precise format the law requires. The voters then printed out the form, signed it and mailed it to Parrott.

The e-mail list generated by that process is now itself an organizing tool for other causes. Parrott won’t say how many people signed up, but many voters agreed to be notified when future petition drives are launched.

“This petition drive really sets new ground rules,” he said of the use of the Web and software.

Parrott and some other Republicans are hopeful that the petition’s success could change how voters in the liberal-leaning state weigh in on the laws passed by their elected representatives.

Daniel Zubairi, a Republican from Montgomery County who led a failed effort to force a statewide referendum on speed cameras in 2009, said what Parrott accomplished is a model for what’s to come.

“The technology is pretty awesome,” said Zubairi, who signed the petition against the tuition break on Parrott’s Web page. “I looked at it and said, ‘This is really cool how they got this to work.’ ”

Voters in Virginia can’t initiate a referendum to overturn a statewide law. Those in the District can if they get 5 percent of registered voters to sign up before the end of a 30-day congressional review period for city laws. (The standard in Maryland is 3 percent of the number of voters who took part in the previous election for governor.)

Maryland’s tuition bill is intended to encourage more immigrants to pursue higher education and to make a statement in the broader fight over immigration. The law allows undocumented immigrants who have been in high school in Maryland for three years and whose parents have filed tax returns to attend community college and, later, a four-year institution while paying the same tuition rates that legal residents do.

The American Civil Liberties Union of Maryland has said that the Internet-based software could make it easier to commit fraud and that it “could also dramatically change the petition process in Maryland going forward, opening many more state and local laws to petition challenges in the future.”

Others note that there is much more than technology at play and that it’s premature to assume other efforts will have the same success. The success of the petition drive, they say, had more to do with the hot-button issue of immigration than with the process itself. “This is not the best case to test that,” said Montgomery County Executive Isiah Leggett (D). The tuition issue “was not one of those that was difficult to generate support for,” he said.

Organizers submitted about 130,000 signatures, more than double what they needed, and election officials have verified more than 96,000.

No one is suggesting that more-traditional ways of gathering signatures are about to be abandoned. After all, two-thirds of the signatures did not come through But activists could be seeing a glimpse of the future.

It was Parrott’s work as a traffic engineer, trying to understand human behavior, that helped him see the way ahead, he said.

“You can’t just put a sign at the exit that says, ‘Here it is!’ ” said Parrott, a freshman legislator. People need help getting where they want to go. Without markers early and often, drivers will just blast past, he said.

His approach on the tuition bill was the same, he said. Arrows on the printouts point to where people must sign and date the forms.

“This is what you get when you mix an engineer with a statesman . . . a process that really works for people on the street,” Parrott said.

On the county level, activists with local concerns have been trying to learn from Parrott’s initial success. Montgomery Republican Robin Ficker, one of the state’s most prolific petitioners, has gathered signatures for more than 20 causes. He’s been spending weekends gathering signatures the old-fashioned way — outside supermarkets, in the heat.

Among his latest efforts are a bid to impose term limits on local officials and another to eliminate collective bargaining for county employees. He met with Parrott last week to discuss how he might benefit from the delegate’s Web experience. Whether he can use Parrott’s technology or ends up looking elsewhere, Ficker said a threshold has been crossed.

“It takes an awful lot of time and perspiration to collect those signatures one-on-one, ” Ficker said. “We’re going to have an online presence. . . . It seems to be the wave of the future.”

Activists in other states have been using the Web to spur signature drives. Some are considering how to take it further. Several states allow online voter registration. In California, where ballot initiatives have been popular, there’s been a debate about whether to allow petition signatures to be submitted online.

Alex X. Mooney, chairman of Maryland’s Republican Party, said future referendums might target gun restrictions or a proposed law that would give library workers collective bargaining rights.

For Parrott, a sense of fate pervaded the fight against the tuition law. He said he had been preparing a campaign to undo a possible same-sex marriage law, but the bill fell just short of passage this year.

“That’s how God had his hands on this whole petition drive from the very beginning,” Parrott said.

To create the Web site, Parrott spent about $2,500 and many late nights working with a volunteer who did the programming.

Unlike in California, where voters and special interests have wielded the initiative and referendum process with few restrictions, there are limits to how far things can go in Maryland.

For instance, although Parrott said a potential gas-tax increase would make a nice target for referendum, “that’s not allowed in the Maryland Constitution.” On the other hand, online petition organizing might have been useful in the earlier unsuccessful bid to block speed cameras, Parrott said. And he’s ready if same-sex marriage is approved.

“You don’t know what can come out of Annapolis,” Parrott said. “Now people are watching, and this is a tool that can be used in the future.”