ST. PAUL, Minn. -- Republican Sen. Norm Coleman is withdrawing 650 ballot challenges that his campaign lodged in the U.S. Senate recount. 

The incumbent's move Thursday surpasses one made by his opponent, Democrat Al Franken, who withdrew 633 of his challenges on Wednesday. Thousands of challenges remain, and they could be pivotal in a race that Coleman was leading by just 316 votes in the latest count. 

A lawyer for Coleman says the campaign is likely to withdraw more challenges but would prefer to do it under terms agreed to with the Franken campaign. An attorney for Franken says both sides should be able to withdraw challenges independently. 

Meanwhile, the state canvassing board scheduled a meeting for Dec. 12 to consider options for absentee ballots wrongly rejected.