The short answer: Do not buy expensive ads that promote yourself and your political objectives.

See this article from the New Republic: The Chris Christie Story Just Got Worse.  An excerpt:

As you may recall, Christie came under criticism during his reelection campaign last summer for having inserted himself and his family into the rousing “Stronger than the Storm” ads encouraging tourists to come back to the Jersey Shore. The ads had been funded by federal Sandy recovery aid, and it seemed eyebrow-raising, at the least, for them to feature beaming pictures of a governor in the middle of a reelection campaign, rather than just your average smiling New Jerseyans. The eyebrows shot up quite a bit further when it emerged that the firm that had gotten the job after proposing to feature Christie in its ads, public relations giant MWW, had bid at a much higher price—$4.7 million versus $2.5 million—than a well-regarded New Jersey ad firm that had proposed ads that did not feature the governor. Making matters even more interesting was that the award had been made by a selection committee led by Christie’s very close longtime aide, Michele Brown, whom Christie appointed to run the New Jersey Economic Development Authority, a $225,000 post.