I don't think a single CTO or CIO, whatever that would mean in the
context of an administration, makes sense whatsoever.
What would make more sense to me would be a collection of people
meeting peridoically in a "roundtable" like format for ongoing general
topics a president should be aware of. Or perhaps a "technology
council" to address specific issues that would benefit an
administration by producing a "recommendation" on that specific issue.