not just a former mayor and a governor...

She was also the chair and ethics officer of the Alaska Oil & Gas Conservation Commission. Beldar has more:

...Gov. Palin's service on the Alaska Oil & Gas Conservation Commission is significant. First, it marks the beginning of what's become a very in-depth exposure to the intersection between government and the energy industry. Alaskans in general tend to be more attentive to energy issues because so much of their state's economy and their state government's budget depend on that industry. But Palin has been focused heavily on energy more or less continually since 2004 — a claim that neither Barack Obama, Joe Biden, or (for that matter) John McCain can make.

Second, although she'd been a reformer and opponent of government corruption/favoritism since her time as a Wasilla city councilman and then mayor, she significantly expanded those credentials — at enormous potential political risk — in her capacity as the Commisson's ethics officer...

Read it all. Her qualifications COMPLETELY eclipse Obama's (and, btw, Biden's). When has Barry ever taken on corruption within his own party?