I wouldnt necessarily say Bellhorn's played himself into the starting job at second base, but he leads the AL in walks, and has an on base percentage over .400 which we all know Theo Epstein loves while batting 200+.
As for trading Wunsch for Bellhorn, it won't happen, mainly because the Red Sox don't need a lefty as they are real high on the former Ray Mark Malaska.
How about Wunsch to the Cubs for one of their pitching prospects ala Jon Garland...