It's surely true that Sarko makes himself out to be part of the "liberal" segment of the French right that Madelin is a noted member of, and they may have (or perhaps will have) some understanding about Madelin's return to ministerial office if Sarko wins the presidential. But Madelin is so ineffably stupid, and long ago wore out whatever positive image he might once have had in public opinion, that I really can't get scared about the prospect of his return. I take Sarkozy for too smart a politician to lumber himself seriously or long-term with such a dummy.
Madelin is, politically speaking, an idiot to be sure, but Sarko is far from it.
My guess is you'll start seeing sub rosa connections made; I wouldn't be surprised if the PS starts making the same sorts of insinuations lefter shades have been making in this regard. In fact, I bet Hollande's been polling and/or focus-grouping on this already.
And now to something entirely more important, the game. Fai de bèn a Bertrand, te lou rendra en cagant