In U.S. politics, the minority leaer is the Floor Leader of the second-largest caucus in a legislative body. Given the two-party nature of the U.S. system, the minority leader is almost inevitably either a Republican or a Democrat, with their counterpart being of the opposite party. The position is essentially that of the Leader of the Opposition. In bicameral legislatures, the counterpart to the minority leader in the lower house is often the Speaker and the majority leader is hence only the second-most senior member of the majority caucus, whereas in the upper house the titular Speaker is often a separately-elected officer such as a lieutenant governor and the majority leader may in fact be the single most powerful member of the majority caucus.