AUSTIN – In a brief to the U.S. Supreme Court supporting tougher voter-identification laws, Texas Attorney General Greg Abbott cited the potential for fraud as a reason to require photo IDs.

He wrote that "serious allegations of voter fraud have persisted, especially in South Texas, for more than a century" and said he has "obtained numerous indictments, guilty pleas and convictions."

Attorneys general in several other states signed on.

Last month, the Supreme Court ruled 6-3 that states can require photo identification without violating voters' constitutional rights.

But there is little evidence that many ineligible voters try to cast ballots, prompting Democrats to accuse Republicans of targeting the elderly, the poor and minorities, who tend to vote Democratic.

Republicans say that the mere possibility of illegal voting merits the change, particularly with a rising illegal-immigrant population, and that the photo ID requirement is not onerous.

Texas Republicans, echoing Mr. Abbott's warning of a vote-fraud epidemic, plan to press the Legislature next year to pass a photo-ID requirement.

Virtually all of the 26 voter-fraud cases Mr. Abbott pursued involve absentee ballots. None would have been prevented by requiring a photo ID at the polls.