Swing vote

Vote that is seen as potentially going to any of a number of candidates in an election

A swing vote is a vote that is seen as potentially going to any of a number of candidates in an election, or, in a two-party system, may go to either of the two dominant political parties. Such votes are usually sought after in election campaigns, since they can play a big role in determining the outcome.

This keyword could refer to multiple things. Here are some suggestions: