And in the wake of the Supreme Court's decision late Tuesday allowing the hand counts to be included in the final total, they are the stacks that could decide the election. There were about 27,000 of these "undervotes" in three South Florida counties, ballots on which no vote for president was registered by machines the first time around.
Some experts on voter behavior say the undervoted ballots with their "dimples" or "hanging chads" are found more in Democratic areas. The reasons are tough to pinpoint, but experts speculate more Democratic voters would be inexperienced or advanced in age.
"Republicans are just better trained voters, it's just one of these quirks," said Dario Moreno, a political science professor at Florida International University in Miami.
Moreno, who teaches Miami and Florida politics, said the precincts where voters tend to make the most mistakes are heavily Democratic ones. In Miami, for example, there's a 2 percent undervote in Democratic precincts, compared with 1 percent in GOP-dominated precincts.
"It's because you have a lot of new voters, particularly newly motivated African-American voters brought out by ... Jesse Jackson, and (U.S. Rep.) Carrie Meek," Moreno said. Jackson and Meek took part in a heavy get-out-the-vote drive this year in Florida's black communities, which are overwhelmingly Democratic.
Recounters painstakingly reviewing 1.7 million ballots in Broward, Palm Beach and Miami-Dade counties have set aside questionable ballots with partially removed or dimpled chads - the pieces of paper in the perforated punchcard ballots. Each three-member county canvassing board will try to divine whether the voter meant to vote for Gore or Bush, if either.
Democrats hold thin registration advantages in Palm Beach and Miami-Dade, but outnumber Republicans 2-1 in Broward County.
Daniel Lowenstein, an election law professor at the University of California, Los Angeles, said while the recount of undervoted ballots is likely to turn up more Democratic votes because of the demographics of the three counties, he's skeptical that Democrats fail to fill out their ballots more often than Republicans.
"The least-educated and least-experienced voters tend to be more Democratic, but is failure to stick a stylus through a hole correctly a function of low educational experience? I don't see why it should be," Lowenstein said.
Lowenstein said it is more plausible that it is a function of age, and all three of the South Florida counties have large elderly populations. In Broward the elderly tend to be Democrats, but in Palm Beach and Miami-Dade they are split more evenly.
The three counties had the largest number of undervoted ballots. In Miami-Dade, tere were 10,750; in Palm Beach, 10,582; and in Broward, 6,686.
More dimpled ballots were breaking for Gore than Bush in Palm Beach, according to Democratic lawyer Dennis Newman, who observed the counting. He said with 140 of 531 precincts completely counted, there were 327 dimpled ballots for Gore and 100 for Bush that were excluded.
Despite Moreno's assertion that more Democrats' votes are thrown out than Republicans, he knows there are exceptions.
"My vote was thrown out," Moreno said sheepishly. He voted by absentee ballot and one of the lawyers involved told him his ballot was rejected.
"My witness didn't put her address on the ballot," he said.