[cnn-photo-caption image=http://i2.cdn.turner.com/cnn/2008/POLITICS/12/19/minnesota.senate.race/art.coleman.franken.gi.jpg caption="Republican Sen. Norm Coleman, left, and Democrat Al Franken have swapped leads in Minnesota's Senate race."]
(CNN) - With somewhere between 1,000 and 2,000 ballots left to be processed, the recount in Minnesota's U.S. Senate race will resume this week and likely will not be resolved until the end of the month, Minnesota Secretary of State Mark Ritchie said Sunday.
A unofficial running tally on the Minneapolis Star Tribune's Web site had Democrat Al Franken leading incumbent Republican Sen. Norm Coleman by 251 votes
on Sunday - in a race in which nearly 2.5 million votes were cast - but Ritchie cautioned against pronouncing either candidate ahead until all votes are counted.
"From the first night of the election - election night, November 4 - it has been impossible to say which candidate was leading because it is not known
who's leading until all the ballots are counted," Ritchie said in an interview with CNNRadio.
"The many people who have been making pronouncements about who's ahead and who's behind are not speaking from a knowledge base. They are speculating."
Ritchie said the state canvassing board has completed the vast majority of the main work in the first round of the recount and board members will meet
Tuesday to finalize vote totals. That will leave between 1,000 and 2,000 wrongly rejected absentee ballots and about 150 overseas ballots left to be processed, he said.
"We had 99.97 percent agreement in the first round, that's with the candidates and the local election officials," Ritchie said.
Ritchie said the final decisions on the ballots left to be processed are due on December 31. The next meeting of the state canvassing board after that
date is scheduled for January 5, Ritchie said.
Asked what would happen if the election is not finalized by the time senators are sworn in in January, Ritchie said, "I don't know.
"It's somebody else's area of law. My only job is determine how the people of Minnesota voted on November 4."
- CNNRadio's Amanda Moyer contributed to this report.