Pardon me, but this seems like a big waste of time. These are states that are already locked down... Send him to Missouri and Indiana.
Maine is kind of funny - Is he trying to help unseat Poliquin or something? Michigan as well. If he thinks he can help flip a number of State House / US House seats for Democrats, I suppose it would be nice, but it should get low priority vs states with remotely competitive US Senate races.
All the other states would be good to have him in for downballot assistance. Maybe Bernie could help drum up support/enthusiasm for Feingold in competitive Senate districts, so as to help flip the State Senate and bring Russ back to Congress.