Minnesota's state canvassing board is meeting Tuesday to review hundreds of disputed ballots, six week after the senate race between Norm Coleman and talk-show host Al Franken ended in deadlock.

The two candidates were virtually tied following the Nov. 4 election, triggering a mandatory recount. As it stands, Republican incumbent Coleman leads Democrat Franken by 188 votes from more than 2.9 million ballots.

Now the state's canvassing board — made up of Secretary of State Mark Ritchie, two state Supreme Court justices and two Ramsey County judges — will inspect roughly 1,500 ballots challenged by the two camps.

The number of challenged ballots had been as high as 6,000, but each side dropped most of their challenges earlier this week.

Ritchie hopes the board can plow through the disputed ballots by Friday.

That leaves the matter of another 1,500 absentee ballots Franken contends were wrongly rejected.

Those ballots contain partially filled out boxes, extra markings or boxes that had been marked and then crossed out in favour of another candidate.

Coleman's camp had challenged the admissibility of the absentee ballots, but last week the canvassing board ruled they should be included.

Lawyers for Coleman have since asked the state Supreme Court to block the board ruling. The court will hear the matter on Wednesday.

At least 638 absentee ballots are known to have been rejected for something other than the four legal reasons for disqualification. That's based on an assessment of about half of Minnesota's counties by the secretary of state's office. State officials estimate the total could top 1,500.

It's not known which candidate stands to benefit most from those ballots.

With files from Associated Press