Alaska is a small state electorally, so she doesn't wield the fundraising numbers or donor influence of a larger state senator. She got elected because of her father's name, and stays elected because she brings home the bacon and greases the correct palms. She was actually primaried successfully and off the republican ticket in a prior election, but came back as a write in candidate in the general and won against a more conservative candidate because of the favors she called in from those greased palms.
If she becomes a reliable conservative vote, she won't be courted by the leadership and offered pork for her constituency.