WASHINGTON (Reuters) - They sued early and often.
Voting-rights advocates, along with the U.S. Department of Justice and some political party officials, tackled potential electoral problems early this election year. Judges blocked stringent voter ID laws, lifted registration restrictions and rejected limits on early voting.
As a result, Election Day 2012 escaped the legal dramas of the past. While some local skirmishes landed in court, no litigation clouded President Barack Obama's victory on Tuesday over Republican challenger Mitt Romney.
But courtroom wars over the franchise are far from over.
Some voter-identification laws were put on hold only for this election. More significantly, the U.S. Supreme Court is poised to consider major disputes - from Arizona and Alabama - at the heart of the right to vote.
"There's now going to be a battle royale at the Supreme Court," said Michael Waldman, president of the Brennan Center for Justice at New York University Law School. The center was one of the groups taking the lead on recent litigation, including on behalf of the League of Women Voters in Florida against restrictions on third-party groups that register voters.
Voting rights advocates have been vigilant in trying to halt practices that could turn away legitimate voters or toss out good ballots, especially since the disputed Florida presidential election of 2000 and the Supreme Court's 5-4 decision in Bush v. Gore. Lawyers for political parties, seeing how elections can come down to a mere hundred votes, have jockeyed for any electoral advantage.
Ohio State University law professor Edward Foley, an election law specialist, said advocates have learned the lessons of past disputed races, including the months-long recount fight arising from the 2008 U.S. Senate election in Minnesota. Democrat Al Franken eventually was declared the winner, by 312 votes, over Republican Norm Coleman.
Foley said litigation this year, notably in Ohio and focused on early-voting rules and provisional ballots, began earlier than in previous cycles. "In some ways it's analogous to the military," he said. "Lawyers are preparing for the last war and what the next war would be."
Much of this campaign's litigation hinged on state attempts to toughen voter ID laws. Proponents, mainly Republicans, argued that new requirements were needed to prevent fraud at the polls. Opponents, mainly Democrats, countered that they burdened minorities, the elderly and poor, who are less likely to have the documentation required for an ID. State and federal judges blocked the most restrictive laws from taking effect.
That chapter is not closed. Texas Attorney General Greg Abbott, for example, has appealed a decision against the state's new ID rule to the Supreme Court. A three-judge federal panel in Washington, D.C. said Texas could not show that the rule would not discriminate against blacks and Hispanics who might live hundreds of miles away from state offices that would issue IDs.
The justices already have agreed to review an Arizona law that would force voters to show proof of citizenship before they could register. The mandate, adopted through a ballot initiative in 2004 and on hold because of the litigation, was intended to stop illegal immigrants from voting
After Indian tribes and civil rights advocates challenged the proof-of-citizenship requirement, an appeals court ruled it conflicted with the 1993 National Voter Registration Act. The standard federal form under that act asks people only to check a box noting whether they are U.S. citizens and does not demand proof.
A potentially more consequential case at the Supreme Court's door challenges a core provision of the Voting Rights Act, a landmark law adopted in 1965 to protect blacks and other minorities historically kept from the polls.
Officials in Shelby County, Alabama - backed by several southern states - are seeking an end to the act's mandate that locales with a history of discrimination obtain federal approval before making any change in ballot rules or district lines.
Nine states and parts of seven others are covered by the Voting Rights Act. Federal challenges to Texas and South Carolina voter ID laws this year relied on the provision.
Yet the current court, which could say as soon as November 13 whether it will hear the dispute, has suggested the requirement may be outdated.
"Things have changed in the South," Chief Justice John Roberts wrote in 2009, the last time the court reviewed the Voting Rights Act.
Editing by Howard Goller and Steve Orlofsky