A federal court yesterday dealt a bad hand to Hillary Rodham Clinton, smacking down an effort to stop Nevadans from caucusing at Las Vegas casinos like Caesars Palace and the Flamingo hotel. The Nevada teachers union, which has strong ties to Clinton, sued with other plaintiffs in Las Vegas this week to halt an effort to let casino cooks, maids and card dealers caucus at nine downtown casino sites. The effort to create "at large" precincts - backed by the state Democratic Party - was aimed at getting more low-wage workers to participate in the election process. Clinton and Barack...