How do preferences work in the Senate?
If two candidates don’t get a ‘quota’ in the first count then the candidate with the least number of votes is ‘knocked out’ and their second preferences are distributed to the remaining candidates. This continues, with each candidate with the least number of votes being redistributed until someone gets the quota needed (one third plus one of all the votes).
If your preferred candidate is not elected then your vote carries on at full value to support the next candidate you have numbered. Your vote is not wasted if you follow the instructions on the ballot paper.
Last election it took until the 25th redistribution for the second senate spot to be filled!