You have to work both sides. Make is easier to bike there first. Get people to bike places. If people decide it is too hard to drive and they don't think they have options (even if they are wrong, what they think matters!) they will vote for politicians who promise to fix the problem. Turning bike lanes into car lanes is a winning message if not enough bikers exist.

There are lots of cities in the world with their own situations. Not knowing the details of where you live means I can only offer the above generalization. Some places have enough alternatives that making driving hard will motivate people who just haven't got around to trying them to finally stop driving. Other places the alternatives are terrible and attempts to make driving hard will just result in a setback for bikes as we lose what little we have already gained.