For a piece of legislation to proceed to the senate, it needs a certain number of votes. whose job is it to organize the votes of the party? the whip the floor leader the caucus the committee

The Whip is the correct answer.

Explanation:

Official of a political party who ensures the party discipline in legislature. HE/she ensures that all the members vote as per the party platfrom instead of doing acting according to their own individual ideology. It is taken from the phrase “whipper-in”

Democrat James Hamilton was the first whip, he was elected in 1913. Whips used to serve as the assistant leaders. They count head and rounds up the member for quorum calls and votes. They also stand for majority and minority leaders in their absence.

a stronger central government  

its what they are