I'm sure its based out of distance reasons rather than political. The engines are kept in Cheyenne, which is only about 100 miles away from Denver.
Norm Coleman is a republican and hasnt been the mayor of St. Paul since 2002. The current mayor, Chris Coleman (No relation) is however a democrat, but Id assume he is more than happy with the amount of money the convention is bringing into his city to worry about a steam locomotive.
Well..Norm is "Democrat light"..which is what I ment..lol.
In St Paul..things are strange..having lived up there.. I would not be surprised if it was politics..but yes, logistics is probably to blame.
Dave C