Forget Nikki Haley, Paul Ryan, and Marco Rubio. The Ohio senator has the right style and background to be Romney's running mate.

Mitt Romney will be the Republican nominee, Wisconsin sealed the deal, and he will pick Sen. Rob Portman of Ohio as his running mate.

Write it down. And harangue me mercilessly this summer if I am wrong.

Column writing, I have learned, is part provocation and part explanation.

There is nothing provocative about declaring that Portman will be Romney's running mate, except that it hasn't happened and I don't know it an as absolute fact.

But everything tells me it will be so.

I'm not suggesting Portman, nor am I advocating for him. I don't know if he will be a good pick or a bad pick. What Romney and Portman make of the ticket is between them and the voters.

Here's why I think it will happen: