Pedestrians have right of way over a bicycle. Even if they are in the bicycle lane, going the wrong way, or just in the way. When you encounter a runner or pedestrian in your way, you should move to the left and pass them on your right (of course, first check for vehicular traffic before moving to the left). Even if this means that you have to move outside of the bike lane to safely pass the pedestrian. If it is unsafe to move outside of the bike lane then it is your responsibility to stop to avoid a collision.

It sucks that runners and pedestrians sometimes hog the bike lane. But it is best to just "let it go" and move to the left. You should also try to do it in such a way so that the oncoming runner or pedestrian sees your intentions ahead of time so that they do not mis-step and go right into your intended path. So, if possible make the move early and obvious.