Sarah didn’t just “endorse” McCain, she campaigned for him, did robo calls for him, and did fund raisers for him. She made it very clear to the republicans in Arizona that she fully backed McCain because he was the most conservative person running.
Everyone and their Momma knew that Sarah was going to support McCain way before JD even entered the race.
She did one or two fundraisers & campaign events for him - and that was way back in the Spring.
The fact that Sarah is being blamed for JD's loss shows just how weak JD's candidacy was.