The huge stack of challenged ballots in the U.S. Senate recount shrank more Tuesday, as Sen. Norm Coleman's campaign withdrew another 475 challenges to match those recently pulled back by Al Franken's campaign.

"We've gotten a positive gesture on the part of the Franken campaign and we want to respond in kind," said Fritz Knaak, the Coleman campaign's lead recount attorney.

Each campaign now has withdrawn more than 1,000 challenged ballots, leaving about 4,500 challenges for the state Canvassing Board to review next week and possibly award to the nearly deadlocked candidates.

Meanwhile Tuesday, counties continued to separate validly rejected absentee ballots from those that were rejected mistakenly or for reasons not specified in law. Sixty-eight counties, along with 14 cities in Hennepin County, have volunteered to sort the ballots.

Few of the ballots were found to have been rejected in error. In Clay County, 21 of 166 rejected absentee ballots were improperly turned down; in Beltrami County it was six out of 100, and in Lyon County it was two out of 52.

County officials said they refused to open and count the rejected ballots, as the Franken campaign asked them to do last week. "We have no authority to do that," said Lori Johnson, Clay County auditor-treasurer in Moorhead. "If the Canvassing Board told us to do it, or a court order, we'll do it."

Margins and missing ballots

When counties finished their recounting last week, Coleman held a 192-vote advantage over Franken, not including the more than 6,000 ballot challenges originally filed, according to Star Tribune calculations.

On Tuesday, Marc Elias, the lead recount attorney for Franken, sharply criticized the 192-vote margin reported by the newspaper as inaccurate at best and misleading at worst.

"It assumes that every single challenge will be upheld by the Canvassing Board. ... Whatever the number is, it isn't 192," he said.

The Star Tribune responded Tuesday that it makes no assumption about the eventual outcome of the challenged ballots. The paper's count shows the margin between the candidates in the ballots that have been recounted, and separately lists the number of ballots challenged by each candidate.

The Franken campaign says their candidate is four votes ahead of Coleman, based on the premise that every ballot challenged by both campaigns will fail. Experts say that, in the end, most of them do.

Elias also chided the Coleman campaign for suggesting that the 133 ballots said to be missing from a Minneapolis precinct are not, in fact, missing. If the ballots can't be located, it will be up to the state Canvassing Board whether to use the Election Day results in their place.

The ballots are important to the Franken campaign because the DFLer won by a significant margin in Minneapolis. Knaak said he was undecided as to whether the Election Day tally should be used in lieu of the actual ballots.

Knaak last week said he expected to meet with Elias about further eliminating challenged ballots, but Tuesday neither man would say when such a meeting will take place.

Kevin Duchschere • 651-292-0164