Neither Dan or Nate!

One thing is who I think it would have been,
the other is who I want it to be.

Serenate <3

Ben. Since he was the last guy she slept with?

I think it would be Nate.. I mean the storyline wouldn't fit if it was Dan, because he is in love with Blair.. And well, it wouldn't make sence either if it wasn't one of the main charaters so.. Nate :)

SHE DIDN'T SLEEP WITH EITHER OF THEM IN SEASON 4.

I know that they didn't sleep together but I want it so much

I would have wanted it to be Nate, but since she did'nt sleep with either Nate or Dan in s4, it would have been Ben's. But they could have made it a Ross and Rachel(Friends) story where when Rachel was pregnant, everyone thought it was Tag's because he was the last guy she was with, but it was actually Ross's. (The rest of the gang did'nt know that R/R hooked up.) The same thing could have been done in GG if Serena was pregnant, where everyone thinks it's Ben's, but it's actually Nate's, since Nate and Serena secretly had a one night stand after her and Ben's relationship was over, just like Ross and Rachel had a one night stand after Rachel and Tag's relationship was over. I think this is what they would have done if they decided to make Serena pregnant, since it would'nt fit to have her pregnant with someone who was'nt a miain character. However, they may have made the one might stand with Dan instead of with Nate.