DENVER -- With nearly 4,000 uncounted absentee ballots remaining, Denver election workers went back to work Monday in hopes of wrapping up long-delayed final results from last week's election.

Denver election officials still must hand-copy 3,820 absentee ballots that were damaged or filled out improperly and then run them through counting machines. They have finished counting nearly 62,000 other absentee ballots.

"Ballot duplication occurs whenever a voter improperly fills out a ballot or if it gets damaged in going through the machines or mail handling," said Denver Elections Commission spokesman Alton Dillard.

Also uncounted in Denver were an estimated 3,000 provisional ballots, usually cast by voters whose eligibility is in question. The ballots are put aside until the voters' status can be verified.

"We're still counting today because we actually counted ballots all the way up through midnight on Sunday, and then sent everyone home to get a little bit of a snooze and got back after it this morning," said Dillard.

Among those anxiously awaiting the final tally were the candidates for Colorado secretary of state, Republican Mike Coffman and Democrat Ken Gordon. As of Sunday afternoon, Coffman had a lead of about 25,000 votes out of more than 1.4 million cast statewide.

Dillard declined to predict when the count might be finished.

"I'm not going to give a time frame. I'm going to go a couple days at the outside to give us some cushion," he said Monday. Last week, election officials said they hoped to wrap up the vote by Saturday. That deadline came and went.

The Denver delays were so severe that police officers were called in Saturday to relieve exhausted election workers.

Also undecided was a Denver tax increase to fund preschool. Supporters for Denver Question 1A anxiously wait for the results.

"We've been working on this initiative for three years. You know, a couple more days, we can hang in there. We're just excited for it to be finished and be able to move on and make this program reality for all of Denver's children," said Initiative 1A spokeswoman Lynea Hansen.

An at-large seat for the University of Colorado Board of Regents is also up in the air. Republican Brian Davidson leads Democrat Stephen Ludwig by a little more than 13,000 votes.

With more than 140,000 ballots counted on the preschool tax proposal, "yes" votes exceeded "no" by about 1,000, Dillard said.

An unknown number of ballots remained uncounted in other counties, including Boulder and Pueblo.

The delays were blamed on computer problems and equipment failures.

Anthony Rainey, technology chief for the Denver Elections Commission, was placed on "administrative investigative leave" Saturday in the aftermath of the election problems.