"X of Y" refers to a type of voting system in which voters are allowed to vote for more than one candidate in a race, rather than just one. Instead of choosing just one candidate, the voter can select "X" number of candidates out of "Y" total number of candidates running for a particular office.
This system is also known as "proportional representation" or "preferential voting" and is used in a number of countries around the world, but not widely used in the United States.
One example of a system similar to "X of Y" in the United States is the ranked-choice voting, which allows voters to rank candidates in order of preference. If no candidate receives a majority of first-choice votes, the candidate with the fewest votes is eliminated, and their votes are redistributed to the remaining candidates based on the voters' second choice. This process continues until one candidate has a majority of votes. This system is used in a few cities and states in the US, like Maine.
The "X of Y" voting system is considered more democratic as it allows for a more accurate representation of the will of the voters and encourages more diverse representation. It also discourages negative campaigning and the need for the "lesser of two evils" mentality.