At this point in their relationship Kerrigan is second in command of the Sons and Raynor is some General/Advisor, he's certainly bleow Kerrigan in the pecking order. They met, through Arcturus Mengsk on Antugua while doing a job for Mengsk - getting the Confedration off of Antigua Prime so the Antiguan Protectorate could join the Sons of Korhal. Let's review Raynor's and Kerrigan's relationship, because a very important question to me is why Jim goes to the length he does to save Kerrigan.
If you haven't played the campaign, get out and stop reading, spoilers ahead.