When Americans go to the polls in November to elect a president, they will confront a voting system beset by many of the same problems that produced the bitterly disputed outcome four years ago and led to a 36-day legal standoff ultimately decided by the Supreme Court.

Several of the most hotly contested states -- including Ohio and Missouri -- make widespread use of the paper punch-card ballots that caused so much trouble in Florida in 2000. Concerns about security and recounts have delayed greater use of electronic voting machines in many states. And a hodgepodge of state laws means varying legal requirements for how -- or even if -- recounts will be conducted this time around.

The delays and changes in election laws have prompted both parties and presidential campaigns to gear up early with legal teams in preparation for Election Day and have left local election officials fearful of a repeat of Florida's experience.

Voicing a concern of many election officials and analysts, Bureau of Elections director Denise Lamb in New Mexico -- where the 2000 race was decided by just 366 votes -- said, "God help us if the election is close."

It was not supposed to be this way now. The lessons of the 2000 election that deadlocked in Florida were as clear as the calls for reform: The nation's system for casting and counting ballots was antiquated, unreliable, often capricious and unable to produce a clear-cut winner in an election with razor-close margins.

In response, Congress passed the Help America Vote Act to assist states in upgrading aging voting equipment, creating more accurate voter rolls and preventing eligible voters from being turned away at the polls.

But election officials and experts say many of the most important reforms will not be in place for the Nov. 2 election in the most closely contested states.

Bureaucratic delays, coupled with concerns about the accuracy and security of high-tech electronic voting machines, mean that an estimated 32 million voters in 19 states will still use the punch-card ballots that left Florida officials struggling to divine voter intent from hanging chads and pregnant dimples.

Because Congress set only minimum standards in the voting law, new at-the-poll identification requirements vary widely from state to state. Adding to the confusion, rules differ from state to state on how and when to count "provisional ballots" that must now be given to voters whose names do not appear on the rolls.

The sensitivity to election irregularities after the 2000 experience means that legal challenges to this year's balloting are all but certain, analysts said. Officials in both parties already have filed lawsuits in several states to challenge election rules.

Barry Richard, a Tallahassee lawyer who represented George W. Bush during the 2000 recount, said he thinks it is unlikely this year's election could again come down to a single deadlocked state. And, he said, this time there would be legal precedents set by the 2000 election to guide the process. Still, Richard said, he has agreed to represent President Bush "should the need arise."

Norman J. Ornstein, a scholar at the American Enterprise Institute, said he believes litigation is likely.

"We've taken a high level of unease, distrust and skepticism about the sanctity of the voting system from 2000 and we've poured gasoline on the fire," he said. "If the election is close, there's going to be ample reason for the losers to point at a variety of issues."

Equipment and Recounts

A top priority of the Help America Vote Act was the replacement of decades-old election machinery with less error-prone equipment that would help voters catch mistakes and provide for accurate recounts.

Many states changed equipment: The percentage of registered voters using electronic voting machines has more than doubled in the past four years while the percentage using punch cards has been cut in half.

But most of the promised federal equipment replacement money was not distributed until June, and the law gives states until 2006 to put new equipment in place. So equipment that was widely discredited in the 2000 election is still prevalent where accuracy could prove most important: in some of the states considered toss-ups between Bush and challenger John F. Kerry.

For example, 72 percent of Ohio's registered voters -- more than 5 million people -- must use punch cards to vote.

And while more people in Ohio will use punch cards ballots than any other state, eight other states projected to be close in the presidential election will also make use of the outdated technology. In Missouri, for instance, two-thirds will use punch-card ballots.

In Louisiana and Pennsylvania, almost half of voters will use even older technology: machines with mechanical levers. The outdated metal boxes, which the federal government is paying states to replace by 2006, are error-prone, easy to tamper with and break down frequently, experts said. Lever machines also will be widely used in such contested states as West Virginia, Arkansas and Virginia.

To some extent, states are keeping old technology because of fear that high-tech electronic voting machines billed as the panacea could make matters worse. Fifty million voters will use the machines, which resemble automatic banking terminals.

But in Ohio, election officials delayed deployment after a consultant found serious security flaws in the technology offered by four of the nation's top vendors. The study found that anyone with a security card and access to voting terminals made by Diebold Inc. could take control of the machines by typing a universal password of 1111.

Security consultants hired by Maryland officials reported earlier this year that they were able to hack into that state's electronic voting systems to corrupt vote counts and delete election results. Maryland is sticking with the system, with officials saying they have tightened security procedures.

Advocates of the electronic machines say security concerns must be weighed against statistics showing that the machines prevent voter mistakes that led to many ballots being canceled.

Critics, however, point to places such as Raleigh, N.C., where 294 votes were lost in 2002 because of computer glitches. The critics' biggest concern is that the machines offer no independent record for a recount, meaning that it is impossible to detect whether there has been tampering.

Those concerns led Nevada to debut a system last month that provides a backup paper record for each electronic vote.

Recounts are not a problem reserved to electronic voting machines.

Most states have no provision to automatically recount any type of ballots in a close election, according to the National Conference of State Legislatures. Some still allow partial recounts, while others insist they be done statewide. Some states have enacted detailed laws governing how and when to count some contested ballots, but at least one hotly contested state, Pennsylvania, does not have a uniform system.

A statewide recount there would require a candidate to petition in 67 county courts. Because the state has no set rule, each court would set its own. The result could be the very type of county-to-county discrepancies that led the U.S. Supreme Court to shut down the Florida recount.

Gov. Edward G. Rendell (D) has said he hopes to change the law in time for November's election. Republican legislative leaders are skeptical, but Rendell spokesman Abe Amoros said change is needed: "We're trying to prevent chaos."

Registration Problems

A Caltech-MIT study found that of the estimated 4 million to 6 million votes lost nationwide in the 2000 election, about half can be traced to registration problems that disenfranchised qualified voters.

Kay J. Maxwell, president of the League of Women Voters, said registration problems could prove to be the "sleeper issue" of 2004.

"There's been so much discussion about voting machines," she said, "but this could turn out to be equally if not more important."

In Pennsylvania and Minnesota, county officials also are concerned that new statewide registration systems designed to prevent fraud could lead to disenfranchisement. Glitches in Pennsylvania's system have made processing new registrations and absentee ballot applications so laborious that officials fear they will not be capable of accommodating a large influx of absentee requests just before the election.

"I don't even want to think about what to do if that happens," said Deena Dean, the elections supervisor in GOP-leaning Bucks County, north of Philadelphia.

Minnesota's new computerized system was rejecting eligible voters because of inconsequential differences between the information applicants put on the forms and existing state records. Officials believe that problem has been addressed, but some worry other glitches could arise when it is too late to fix: Election Day, when two-thirds of the state's voters register.

"Unfortunately, we're going to have to test this system in combat," said Joe Mansky, election manager of Ramsey County, which includes St. Paul.

Another registration problem that emerged during the 2000 Florida recount was that state's use of a flawed list to purge dead people and felons from the voter rolls that wound up disenfranchising thousands of eligible voters. The state was set to repeat the mistake until news organizations revealed that the 2004 list was similarly flawed. Florida scrapped the statewide list, leaving it up to each county to decide whether and how to purge ineligible voters.

ID Requirements

Meanwhile, related questions have arisen in another state. Prison advocates have filed suit in Ohio, charging that election officials are giving misleading information to felons about their voting rights.

Perhaps the most partisan disputes to emerge this year have centered on new voter identification. In general, Republicans support ID requirements to prevent fraud, while Democrats say such requirements disproportionately disenfranchise poor and minority voters who may not have a driver's license, a utility bill in their name or other acceptable documents.

Striking a compromise, the Help America Vote Act mandated that any first-time voter who registers by mail must either include a copy of an acceptable ID or show it at the polls. States, however, were free to go further, and as a result the nation now has a confusing hodgepodge of identification laws.

The Republican-controlled states of Florida and Missouri are among 17 that require all residents to produce identification when they vote. By contrast, New Mexico's democratic secretary of state decided to require only the bare minimum, prompting a Republican lawsuit.

At issue is the Republicans' contention that thousands of new voters who registered during drives conducted by third parties are, in effect, registering by mail and therefore should be subjected to identity checks at the polls.

State election officials contend that expanding the identification requirements now would produce Election Day chaos, as well as disenfranchise Native American voters who may not have the type of ID required.

That already happened during South Dakota's June primary, when poll workers confused about new identification requirements failed to tell Native Americans they were allowed to sign an affidavit in lieu of showing an ID.

That in a number of swing states only some voters will be required to produce identification is likely to lead to charges of discrimination -- founded or not -- and a flurry of Election Day court filings, said Doug Chapin, director of Electionline.org, which tracks changes in balloting equipment and methods.

"In the current environment," he said, "any little thing that generates a spark will produce a fire."

Provisional Ballots

One of the most popular post-Florida reforms contained in the Help America Vote Act was a mandate that all states give voters a provisional ballot when they arrive at a polling place and their names are not on the rolls. Voters who feel they are the victim of a registration error can cast a ballot, and election officials can research their eligibility after Election Day.

But the reform is creating a host of new problems that have already led to lost ballots, contested elections and legal battles.

"Provisional ballots will be the hanging chads of 2004," predicted Ralph G. Neas, director of the nonprofit People for the American Way Foundation, a liberal organization that has been working for voting law change.

Some states, including seven that are contested, refuse to count a vote for president, even if the voter is eligible, if the ballot is cast in the wrong precinct or congressional district.

That has already caused problems: Of the 5,914 provisional ballots cast in a recent Chicago race, only 416 were counted. Most were disqualified because election officials allowed voters to cast the ballots in the wrong ward or did not ensure that forms were properly filled out.

Experiences such as that led Ohio Secretary of State J. Kenneth Blackwell (R) to reverse course last month and allow provisional ballots cast in the wrong precinct to be counted. "It's ridiculous to penalize a voter for an election official error," Blackwell spokesman Carlo Loparo said.

Not everyone agrees. Labor unions and the Democratic Party have filed lawsuits in Florida and Missouri challenging the validity of similar provisions. Meanwhile, some election officials worry that provisional ballots will not be counted at all.

Verifying voter eligibility and hand-counting provisional ballots is time consuming -- time that election officials will not have in some states. Florida officials, for instance, set a two-day deadline for verifying those ballots, which local election officials have objected to, saying it is not enough.

If the margin of victory in this year's presidential contest is smaller than the number of provisional ballots cast, Leon County election supervisor Ion Sancho said that could lead to the same scenario that caused the 2000 debacle: counties pleading for more time to count, and the secretary of state saying no.

"If you had a thousand of these cast, there's no way we could do the research and comply with the deadline," he said. "I can definitely foresee a circumstance where litigation could occur."

Punch-card ballots, such as this Chicago example from 2000, are still at large despite the election standoff in Florida that went to the U.S. Supreme Court.