Good news. I like Portman, he seems to be the centrist sort of thinking person focused on development and providing quality government services rather than a paranoid right-winger.
I could see myself voting for Portman, though I disagree with your assessment that he's a centrist.
On economic issues, he definitely isn't. I don't know that I'd even call him a centrist so much as someone who is great at sounding like a centrist.
Centrist in relative terms, that is. Moderate in temperament and all that.
Anybody to the left of Ted Cruz is now a moderate.