Incumbency advantage or abuse of power?

[Amy]

http://www.nytimes.com/roomfordebate/2012/09/20/when-the-white-house-speaks-on-the-campaign-trail

How have presidents used executive power to get re-elected? Is this an abuse of power, or just the usual “incumbency advantage”?

http://www.nytimes.com/2012/09/20/us/politics/obama-exploits-familiar-junction-of-policy-and-politics.html?_r=1&pagewanted=all

At what point does enacting last-minute policies cross the line? Or is the incumbency advantage an accepted tradition?