It isnt the majority vote that would win in this voting system every time, so you won't be forced to play the "popular" maps. But it would increase the chance.
For example you have 4 maps that come up. Sewer, mansion, town, garden in a 2v2.
2 people vote for garden, 1 votes for mansion and 1 votes for sewer.
There is a 25% chance it will be mansion, 25% chance it will be sewer and 50% chance it will be garden. Each vote has an equal stake.