And some of the nation's largest jurisdictions ? Los Angeles, Chicago and Greater Miami ? are headed toward voting on paper.

"Could it be a sign of things to come? I'm not sure," said Sean Greene, research director for the nonpartisan reform group Electionline.org.

A real test of whether the nation's big urban places are moving away from electronic voting could come today in Alameda County as supervisors consider a voting-system upgrade.

The same county supervisors who three years ago spent $12 million on Diebold touch-screen voting machines and turned the county into a West Coast e-voting pioneer are weighing whether to invest more heavily or trade in for a paper-based optical scanning system.

That makes this morning's hearing a battlefield, with Texas-based Diebold Election Systems sending top executives to keep their foothold here and a coalition of e-voting critics arguing the company and its products are not trustworthy.

Alameda County Registrar of Voters Elaine Ginnold wants Diebold's latest touchscreen, called the AccuVote TSx, a lighter, fuller-functioning version of the county's existing AccuVote TS machines that also can print a paper record allowing voters to confirm their choices.

Full paper-based voting, Ginnold argues, is costly and cumbersome. Conducting a primary election in her county requires at least 33 different ballots for each precinct ? one for each of eight parties, plus three cross-over parties, all in three languages. Paper ballots also can be imprecise, subject to bad or ambiguous markings by voters.

Electronic voting offers certainty, Ginnold said. Either a vote is for a candidate or not, a yes or a no ? something that elections officials like.

But if Ginnold thinks paper-based voting systems are a thing of the past, they also could be the future. Absentee balloting, or voting by mail, is growing fast in California, with more than half of voters in some jurisdictions mailing in their paper ballots. In 2004, more than 207,000 Alameda County voters ? almost a third ? voted by mail. And Ginnold suspects the convenience of the method will grow in appeal.

"I think it's going to grow big," she said. Within five or 10 years, she expects more than half of the county to vote by mail, on paper.

Critics of electronic voting are seizing on this trend in urging Alameda County to Diebold and the proprietary vote-counting software at the heart of its electronic voting machines.

Swapping 4,000 of the older Diebold machines for the new TSx would cost an estimated $5.4 million. Changing back to paper ballots, with optical scanners in each polling place supplied by Diebold, would cost $3.2 million to about $5 million, Ginnold said. Dropping Diebold for an entirely new voting system and a new vendor would cost twice as much, she said.

Either way, some form of electronic voting is likely to remain in Alameda County and the rest of the nation. The federal Help America Vote Act requires at least one handicapped-accessible voting machine in every polling place by January, and most of the available options for complying are either touch-screen voting machines or electronic machines that mark a paper ballot.