Palin was an intentional "accident" invented by Karl Rove as an attempt to equal or best the Democratic ticket which had a woman running for President. Bobby Jindle was also a Republican response to the Democrats having a dark skinned candidate.

A day before Palin was announced Karl Rove spoke of the Republican party introducing a soft Republican woman into the area of Presidential politics. You see they always portrayed Hillary as shrill and hard edged so they would have a soft curvacious alternative to Hillary in Sarah.

As we see now, not much thought or vetting went into their desperate decision to throw McCain the female vote.