Winning the locals, energizes your local party - allows you to pick up new volunteers, new ideas and to solidify the supporters you have locally without the cacaphony of national issues which can have a dramatic effect in a local area.   Most important though: winning local elections creates (hopefully) your bench of candidates for the future.  How many mayors used to be city council members or board of education chairrmen? etc.

That said - I live in Danbury, Connecticut and we are working very hard to take back a Democratic City from a Republican mayor who has done virtually nothing except cut ribbons on projects started by his Democratic predecessor. 

Any one local to my area and who wants to get involved, post a reply and we can get in touch.  Everyone else: what is the state of the local elections?  are we picking up mayor's officers or city councils etc?  what is the general mood of the voters in your area?