WordNet
n. the legislator who organizes his party's strategy
Wikipedia
Floor Leaders are leaders of their political parties in a body of a legislature.
Usage examples of "floor leader".
In the latter case this is a cue for your unofficial floor leader to move to refer to committee.
The Speaker of the House has still not commented, but his floor leader and the nominated minority leader appeared with the President when she announced her choice.
There was a crowd around the desk of the administration floor leader and a smaller cluster around the floor leader of the opposition.
As soon as the connection was made again with Frankfurt, he would ask the President how much he could concede to the opposition floor leader in return for his full support of AUP.
I don't know whether the floor leader shook his head or signaled, but he did not take the floor.