Campaign for Tokyo Mayor

We haven't figured out the purpose of these boards yet.  They appear in various places throughout the city including outside our apartment building.  Doug thinks they may serve a political purpose; perhaps these people are running for government office?  (I think they may be on Japan's most-wanted list.)  If these are candidates for political office, what an orderly and sane way to go about advertising! 
Update:  Yes, this is a political campaign, and it is a big one.  There are 16 candidates for mayor (governor) of Tokyo though these boards only show the top few.