Latino leaders in Nevada and nationwide are quietly debating whether to sever their traditional Democratic ties and form an independent grass-roots political group. The idea, born of frustration over the party’s inaction on immigration reform and fears that as a voting bloc they’re a political afterthought, Latino leaders have discussed the idea among themselves locally and in conference calls with colleagues across the country. The unlikely model for the movement they would like to launch is the Tea Party — not in substance, of course, but in its grass-roots organizational style. Acknowledging the source of their inspiration, Latino leaders have...