Palin did get some good conservative candidates elected to various offices, but beyond that she can't directly deliver.
Look at Romney. He got 60 million people to vote for him to Obama's 65 million, yet you don't hear a peep from Romney.
Why didn't he try to parlay that support into a faction to give him a platform from which to speak? Instead, he just slinks away as if none of it mattered?
Romney could have been speaking out publicly on the fiscal cliff, even after losing the election by a few points. He still speaks for 60 million people, which is more than Boehner or Reid could say.
Right now, Palin just speaks for herself. To be relevant, she needs to convince a few million people to vote for her again, and then get into a federal body where she can deliver directly.
-PJ