The main reason is because the other day when Rafe mentioned inviting the baby’s father to the party, Jordan snapped and said he wasn’t part of David’s life. Therefore I am deducing it’s not Rafe. It could be Ben, but she did invite him, although why has she been adamant that Ben have no contact with David? It could be Clyde. She’s not biologically related to him, she despises him, and he hasn’t been around in quite a while.
No matter who the daddy is, I feel like the big surprise will have a big effect on Ben. It’s going to tie up the reason why she’s kept David from Ben all this time.