Mike,

The Moroun bridge is not the DRIC, the Ambassador Bridge is different name [[cant recall right now).

"Who is opposed?" to a twin span, Answer... Canada. They've already stated it's NOT going to happen.
http://partnershipborderstudy.com/faq.asp
in the faq's Q11: Why was a second span of the Ambassador Bridge dropped from the DRIC study process?
When a twinned Ambassador Bridge was evaluated as part of the DRIC study, the DRIC Steering Committee, composed of representatives from the four cooperating governments, concluded that the social and economic impacts of widening the existing approach road on the Canadian side of the border were unacceptable, and that continuing to concentrate all the border traffic into one corridor, with one set of plazas failed to create the redundancy necessary to address economic security concerns.