For all elected representative elections we use the Alternative Transferable Vote (ATV) system. This means voters can rank candidates in order of preference, so their favourite candidate would be ranked number 1, second favourite would be number 2 and so on. Voters can put numbers next to as many or as few candidates as they like!
When the votes are counted, a formula is used to determine the winning quota required to be elected, this is normally 50% of the total vote plus one. If no candidate has reached quota, the candidate with the least votes is eliminated and their further preferences are redistributed to remaining candidates. This is repeated until a candidate reaches quota.
So even if a student knows who they’re giving their first vote to, you should try and convince them to make you their second choice!