The Nevada affiliate of the National Education Association is obviously feeling some heat for its decision to file suit to protest new at-large precincts at casinos on the Las Vegas Strip that will make it easier for workers to vote during Saturday’s caucus.

The Nevada State Teachers Association is defending itself on its Web site, maintaining that their suit isn’t about drowning out the voice of the state’s largest union, which represents culinary and other workers in the casinos (and happens to be endorsing Illinois Sen. Barack Obama.) Instead, the lawsuit complains of inequalities—that teachers are not afforded the same opportunities to vote in their workplace, their schools, according to the Web site. While the union hasn’t endorsed in the race, many of its top officials support New York Sen. Hillary Rodham Clinton.

And now, 15 teachers and members of the union have written a letter—distributed by the Obama campaign—complaining about the lawsuit. They maintain that the lawsuit, in effect, could squelch the votes of their students’ parents.