I just call the bet on the turn and see what happens. Top pair in a multiway pot with two callers after the flop and you've shown strenght the whole way is a very bad situation. I don't think you can fold for just $4.5, but I don't like putting a whole lot of money into this either. I can easily see someone having K-Q here. And maybe someone flopped a set. I just call the turn and see. If the guy behind raises, you can probably just fold especially if the first guy calls also.

So I would call the smallish bet but be looking to get out of this hand if anyone wakes up and starts betting real amounts. Top pair is just not good enough in a multiway pot when the action starts heating up.