Get Palin to support the strongest of the challengers.
Interesting request. I think she should refrain from doing that. Either way, she loses, IMHO.
If she supports her former running mate (a nice, solidly Republican thing to do), she risks alienating all but the most die hard Palinistas.
If she calculates wrongly on which of the two challengers is strongest, (in other words, she backs the loser) she risks alienating the Republican Party (Ok, like she hasn't already done that on her own) thus potentially jeopardizing her supposed "front-runner" status.
Like I said, you made a very interesting request.