Being a junior Senator is not.
Palin has much more experience than Obama at running a government, and she did a more effective job crafting and passing legislation - as a non-legislator - in Alaska than Obama ever did in the Illinois statehouse or the US Senate.
She knows how to do Obama's nominal job - legislating - better than he does, plus she is an effective executive.
To say that 19 months executive experience of a lightly populated state is more experience than over 40 months as a Senator is not credible. A Senator deals with vast array of national issues with the President. Several good Presidents never served as governor, but instead came through the United States Senate. In contrast, Clinton and Carter, two disgraced Presidents, were governors. Your “executive experience” argument being the paramount and primary qualification would disqualify Kennedy, Nixon, and Lincoln, three brilliant men, and proclaim Clinton, preeminently qualified.