It means that either she looked them in the eye and LIED to them, or she actually thinks that McCain is a conervative and a member of the tea party.
Look, the guy lost his Congressional seat in 2006, a Republican-leaning district. What does that tell you?
Stop using Sarah as a strawman. It was political courtesy for her to endorse & support McCain. Saying he's part of the Tea Party was a warning shot to McCain to stop the reaching across the aisle shenanigans or else she won't bail him out in the future.