In Australia we use a preferential system, meaning we can indicate our first, second, third, etc preferences. Essentially it says "I want A to get in, but if they don't them my vote goes to C, if not them, then D, etc"...
Once the first round count has been tallied the candidates with the lowest number of votes are culled and their votes are then distributed by second preference, and so on until you have a winner. In some seats it never matters much because the candidate is very popular and it is cut and dried, in others the preference flow can make all the difference.
It generally yields a result close(ish) to the overall voting intention but it's still open to manipulation and in our national senate we might end up with some representatives who only got 0.1% of the primary vote but benefitted from the preference flow. That's more an issue with how preferences can be allocated between candidates (where a voter only votes for one or a few candidates rather than the whole field) and not the system itself. I kind of wish they'd fix that because it usually results in total crackpots taking the final couple of seats.