As the 33,7000 members of the transit union meet this week to decide whether to accept the terms of a new contract, they will also have to contend with a new electronic voting system that some worry could be confusing or susceptible to fraud.

The Transport Workers Union Local 100, like every other union in the city, has always used a mail-in paper ballot to ratify contracts. The union’s decision to have members use phones and the Internet to vote will save it thousands of dollars that will help offset the $3 million in penalties levied during the illegal three-day transit strike last month.

Those who plan to vote against the contract feel the voting system would be hard to monitor. “A lot of guys are worried that it could be used to manipulate the process,” a union vice president, John Mooney, said. “We don’t trust any part of the process, especially since there’s been no discussion. It’s something that’s been thrown at us.”

The union’s president, Roger Toussaint, told reporters yesterday that critics’ attacks were aimed at creating political unrest within the union as it faces an election later this year.

“There are elements within our union who are focused on their own political agenda,” Mr. Toussaint said. “They are trying to turn the member ship against the contract.”

A union spokesman, Dave Katzaman, said the decision to go with electronic and phone voting was made by the union’s election committee and did not have to go through the executive board.

The new voting system is 30% less expensive to run than having members mail their ballots, each of which had to be individually opened and tallied, according to Jeff Zaino, a vice president for the company running the election, American Arbitration Association. Instead of a ballot, members will receive a personal identification number, which, along with the last four digits of their social security number, will permit them to vote. Mr. Zaino said this process ensures each member’s vote is accurately counted and tracked.

“It saves money, and you do get instantaneous results,” he said.

The savings of about 85 cents a member could total close to $28,000.

Union leaders will meet tonight for the third straight night to discuss the contract. Members will have until January 20 to vote on the contract, which includes average annual pay raise of 3.5% over 37-months. Workers will have to pay 1.5% of their wages toward health benefits. As many as 20,000 workers could receive an average of $10,000 in one-time refunds from pension contributions they made between 1994 and 2001.