UW-Madison students will vote beginning Monday on a $60 million addition to one of the main campus gyms, a project some students and officials say is needed to keep up with student demand and fitness trends. The expansion, which would nearly double the size of the Natatorium, would cost students $54.19 more per semester for the next 30 years, beginning in 2013. “Someone has to step up so that future generations can have access to the facilities that we never had,” said Mike Bernatz, a student who is leading the campaign for the project, called NatUp. A faction of students oppose raising student fees for the project, but the greatest foe for supporters could be low voter turnout over the three-day-long election.