TALLAHASSEE, Fla. (AP) - A Florida judge has rejected a challenge to the rules that will be used in a hand recount in the state's contentious U.S. Senate race.

U.S. District Judge Mark Walker late Thursday ruled against Sen. Bill Nelson and Democrats in another one of the lawsuits surrounding the recount.

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During the hand recount, election officials look at just the ballots that weren't recorded by voting machines.

Under state law, voters must use only approved markings or their ballot is disqualified. And they can't simply cross out a mistaken vote but must explain in writing why they did so. The lawsuit contends that has a discriminatory effect on non-native English speakers and illiterate voters.

But Walker found the rules were reasonable and constitutional.

Florida counties must finish the hand recount by Sunday.