The election board shall determine the eligibility of any written claim to vote presented to it by one whose name does not appear on the official list of registered voters as well as any written challenge of the right to vote of anyone whose name is on the list. Its decision shall be final. It shall rule on all claims no later than ten days before the election. Any claim not presented at least ten days before the election shall be disallowed. Nonresident claimants successfully appealing omission from the list shall immediately be furnished an absentee ballot. Omission of names from the voters list due to late registration, if notification (pursuant to Sec. 81.14) has been timely mailed, shall not be considered grounds for challenge.