With the warning that "the polling place is about to be abducted by aliens, " an election watchdog group this week released a study cautioning policy-makers against blindly backing Internet voting without carefully assessing the potential for fraud.

The 30-page study by the Voting Integrity Project, a nonprofit, nonpartisan group that tracks voter fraud cases, is one of the first signs of the backlash that will inevitably greet the increasingly popular concept of Internet-based voting. It was presented to the American Legislative Exchange Council, a state legislators' group, which was assembled in Atlanta.

Deborah Phillips, president of the group, predicted a fever among state legislators to embrace the attractive voting technology in coming years.

"All it would take would be for one of those states to decide to do this, and there will be a rush," she said.

The Voting Integrity Project was formed in 1996 in response to the National Voter Rights Act, which allowed voters to mail in voter registration forms. The group trains poll-watchers and has filed lawsuits in Oregon, Texas and Tennessee challenging mail-in voting programs and questioning the legality of voting before Election Day.

Phillips's chief concern about voters casting ballots away from the polls is that outsiders have more opportunity to coerce votes without being observed.

"As VIP advocates," she wrote in her report, "the role of the citizen poll watcher is essential to voting integrity. But now, the polling place is about to be 'abducted by aliens.' Comic images aside, truly independent oversight of elections becomes problematic at best when elections move into cyberspace."

The study presented other troubling scenarios for Internet voting systems.

One of the biggest problems with Internet usage -- system crashes caused by overload -- could be the greatest enemy of large-scale elections online, the report said.

"What would be voter response if there is delay or difficulty accessing their Internet election site?" Phillips wrote in the report. "Would they try again? Once? Twice? If unsuccessful would they then venture to their local polling place?"

Other issues raised by the report centered on the problems of system security and user privacy.

She cited a recent hacking of the Web site for the United States Senate, which diverted visitors to a parody site. With such diversion tactics, the report said, "the frightening thing is that voters would not necessarily be aware their votes were not being legitimately cast. Once diverted to such a counterfeit site, their voting transaction could be captured and used to log votes for the thieves' candidates of choice on the real election site, quite possibly without detection."

So far in debates of Internet voting, proponents have been the most visible.

Another concern was the potential use of Internet user information collected online to manipulate elections. "For example," the report said, "if all Internet users in a particular voting jurisdiction who had frequented anti-tax Web sites could be electronically prevented from having their votes counted in an election on a new tax referendum, or diverted to a bogus election site, which would not count their votes, it could illegitimately allow that referendum to pass."

Phillips, former chairwoman of the Republican Party of Arlington County, Va., drew on a variety of experts to help with the report: Lorrie Faith Cranor, a research scientist with AT&T Labs; John Seibel, president of TrueBallot Inc., which makes election systems for unions and associations, and Hans Von Spakovsky, an election commissioner in Fulton County, Ga.

Cranor, who has studied both the technical and policy considerations of Internet voting for AT&T Labs, described a breathless atmosphere among policy-makers.

"There's a sense of state pride, that 'we could be the first to do this,'" Cranor said in a phone interview on Friday. "I think states should not do this just because it would bring glory to their state. Doing it for glory or just for the sake of doing it is not really what they should be doing."

A few state legislatures have begun to address Internet voting. Bills to initiate studies of the concept were introduced this year in the Minnesota and Washington legislatures. In March, California's Secretary of State, Bill Jones, convened a task force to study the issue and make recommendations to the Legislature later this year. Florida election officials had planned to test online voting systems this fall, but the project was delayed indefinitely because of voter fraud in that state.

On the Federal level, the Pentagon is sponsoring a pilot program through the Federal Voting Assistance Program to allow overseas residents of five states -- Florida, Missouri, South Carolina, Texas and Utah -- both military and civilian, to vote via the Internet in 2000.

So far in debates of Internet voting, proponents have been the most visible.

Jim Adler, president of Votehere.net, a company that makes Internet voting systems, stressed that the technology is ready to detect and deter hacker attacks.

"We don't agree entirely with the report," he said. "But bringing up the issue with security is important. We believe the bar has to be held high. We believe the problems are solvable."

Some of those who have been haggling with the issue of Internet voting welcome the new voice in the debate. Kim Alexander, a member of the California Internet Voting Task Force, praised the Voting Integrity Project for raising new issues.

Alexander, who has long been involved in California politics as president of the nonprofit California Voter Association, started out on the state task force favoring Internet voting but after discussion, has come to oppose it. The task force is expected to release its own report on the issue later this year.

Alexander said she was concerned about the potential for employers to coerce employees who vote online in the workplace.

"If you think about Internet voting for five minutes, you think, 'Why not?' " she said. "If you think about it for a couple of hours, you can think of a lot of reasons why not."