There are more than enough science-dependent issues in presidential politics to warrant a live presidential debate focused on those issues. A live debate would be much better than simply submitting written answers to questions. Read the answers the two campaigns submitted and you will see why -- they only sort-of answer the question, and as quickly as possible turn their answer to their campaign's talking points.
MORE: http://www.skepticblog.org/2012/09/10/science-debate-2012-answers/
See also...
The Top American Science Questions: 2012
http://www.sciencedebate.org/debate12/