Sen. Charles Schumer, chairman of the Senate Rules and Administration Committee, said the study, while providing only a snapshot of voting patterns, "is enough to show that the balloting process for service members is clearly in need of an overhaul."
The committee, working with the Congressional Research Service, surveyed election offices in seven states with high numbers of military personnel: California, Florida, North Carolina, Pennsylvania, Texas, Washington and West Virginia.
It said that of 441,000 absentee ballots requested by eligible voters living abroad
-- mainly active-duty and reserve troops -- more than 98,000 were "lost" ballots that were mailed out but never received by election officials. Taking into account 13,500 ballots that were rejected for such reasons as a missing signature or failure to notarize, one-quarter of those requesting a ballot were disenfranchised.
The study found that an additional 11,000 ballots were returned as undeliverable.
Schumer's office said that because a person living abroad must request the absentee ballot and show a clear intention to vote, voter negligence is not thought to be a major factor.
Rather, the New York Democrat said in a statement, there is a chronic problem of military voters being sent a ballot without sufficient time to complete it and send it back. He cited estimates that a ballot can take up to 13 days to reach an overseas voter.
Among the states surveyed, California had 30,000 "lost" votes out of 103,000 ballots mailed out. An additional 3,000 ballots were returned as undeliverable and 4,000 were rejected.
The hearing was to take up possible problems in the Federal Voting Assistance Program, a Pentagon program that handles the election process for military personnel and other overseas voters.