I'm the dealer holding this:





Upcard is

Everybody passes first round. Second round, the first two seats pass. You're in third with this:





What would you do? It's pretty obvious that if you pass then I'm going to call spades and get a really easy 4 point loner. But assume you don't know my hand? Assume above average players in every position. What would be the thought process going through your head?
BTW, in this particular game, the third seat crossed the river and called clubs, which screwed my loner. He actually managed to make the point too!