The American Civil Liberties Union announced today that it has filed a federal lawsuit against Michigan electoral officials over what the organization characterizes as two "statewide voter purge programs" that it claims would "disenfranchise hundreds of thousands of Michigan voters"—many of them college students—in advance of the fall presidential election.

The legal action comes two days after Democratic nominee Barack Obama's campaign and the Democratic National Committee filed a lawsuit against Michigan over another voter-exclusion practice—using home foreclosure lists to challenge a person's right to vote.

The lawsuits suggest that ballot battles in the key battleground state have just started to heat up.

The ACLU suit, which targets Michigan's Secretary of State Terri Lynn Land, a Republican, as well as the state's elections director and the city of Ypsilanti's clerk, charges that two practices by the state are illegal: one in which the state immediately cancels the voter registrations for individuals who obtain a driver's license in another state, and one in which local clerks nullify new voter registration applications if mailed voter cards are returned by the post office as undeliverable.

"Students and young adults generally are much more transient than older adults, are much more likely to have driver's licenses from different states than their college, and are much more likely to live in multi-unit housing, such as dormitories and apartments," says Jonathan Doster, field organizer for the United States Student Association, a plaintiff in the ACLU complaint. "It's just not fair to deny someone the right to vote just because they are an out-of-state student or they don't get a piece of mail."

Michigan Republican Party chief Saul Anuzis has dismissed the Obama campaign's complaint as "a stunt."