I don't think that Margie and Luke win because I think CBS would have hyped them more before the race instead of focusing on the race route.
Next, I'll use some numerology.
Tammy is the second hottest Tammy in TAR history.
Tammy is the second hottest Asian woman in TAR and
Therefore, she and her brother will come in second.
That leaves Cara and Jamie as the winners.
My only problem is that I don't beleive in mumerology.