Most pundits seem to refer to coattails as a top down affair, the Presidential candidate getting all the media attention and either helping or hurting down the ticket.
I think this is an incomplete way to look at it.
Coattails need to work both ways. The Presidential candidate of course gets the big media attention, but it is the local office holders and party officials who need to be working at getting the vote out.
I'm not saying that a State Senate candidate in, say Pennsylvania, should be defending or speaking on behalf of John Kerry, but I do think it is important for said State Senate candidate to work with local party city councillors, school trustees and mayors to build an effective GOTV organization.
I think this is what Howard Dean is getting at with his new organization.