Why bother? Its doesnt give Democrats anything extra. This is just as stupid as it was when Obama was still campaigning for himself in 2008 when it was clear that he was going to win easily in October, rather than campaigning for downballot Dems.
No, it wasn't. Maybe it would have been advantageous for the Democratic party as a whole, but Obama wasn't in such mortal lock territory that he would have been comfortable doing that.
Remember there was still a glimmer of hope for McCain poaching Pennsylvania and holding all the non CO/NM bush states. It wasn't a done deal till 9:00