sure as can be

Now, it is of no use for you to deny it, for I feel as sure as can be that you have been giving me some medicine on the sly these last few days.”

I'm as sure as can be that if Obama had said something like that, Gingrich would cite it as proof-positive that he's building a Chavista-Alinskyite-socialist-revolutionary machine.

You see I must use it as sure as can be.

Widow Brown immediately screamed out, "Alas-a-day! as sure as can be, here are my red-streaks; I could swear to them in any court."

But, then, to marry my daughter for the convenience of frequent opportunities—I'll never consent to that: as sure as can be, I'll break the match.