Carla Bruni has made an appearance "en tant qu'artiste" in support of Nathalie Kosciusko-Morizet's troubled candidacy for the office of mayor of Paris. This is interesting for two reasons. First, before her marriage to Nicolas Sarkozy, Bruni was a friend and supporter of the current mayor, Bertrand Delanoë, who is backing NKM's rival, Anne Hidalgo. Second, there is a full-blown fronde against NKM within the Paris UMP, so Bruni's appearance should probably be taken as a tacit endorsement by Sarkozy of NKM and a rebuke to her detractors.
In the contest for the 2017 presidential nomination, NKM, whose own hat will probably be in the ring (if she wins in Paris) but who is unlikely to win the nomination, will therefore owe a debt to Sarko. But perhaps just as significant, NKM's enemies will have an ax to grind against the former president.
On balance, Sarko probably comes out ahead, but I wonder what the advisors who want him to continue his veer to the hard right would say, since NKM is anathema to the FN. Of course, sending his wife out as his proxy would be a way of splitting the difference. Unless, of course, Carla went out on her own, without the approval of "mon mari," in which case we'd have to wonder about the state of yet another high political marriage.