President Francois Hollande's partner has set the French political establishment aghast with a tweet seen as a dig against his ex-partner.
The tweet of support to Olivier Falorni, a politician in western France, was signed by Valerie Trierweiler and went viral on the internet and dominated news shows.
It was seen as a dig at Segolene Royal, the mother of Mr Hollande's four children. Ms Royal, also a former Socialist presidential candidate, is running against Mr Falorni in the Charente-Maritime region in Sunday's parliamentary elections final round.
The tweet starts: "Have courage, Olivier Falorni." But it is easily interpreted as a not-so-veiled dig at Ms Royal.
The Socialist Party recently banished Mr Falorni for failing to step aside in favour of Ms Royal, so he is running as a dissident candidate. After last Sunday's first-round vote, Ms Royal holds a narrow lead over Mr Falorni.
Ms Trierweiler, a journalist and avid tweeter, has made no secret of her determination to retain her independence, or of her discomfort with the image and chores of a first lady.
Her employer, Paris-Match, barred her from working as a political reporter after the May 6 election of Mr Hollande, although it has allowed her to stay on as a book reviewer.
Her first review, published last week, was of a biography of Eleanor Roosevelt, the wife of ex-US President Franklin D. Roosevelt, and began: "Look at that! A journalist first lady isn't a novelty."
Television news coverage was dominated by the tweet, along with speculation about why Ms Trierweiler would make such a bold foray into the political arena that risks bringing discredit to Mr Hollande - and is indirectly aimed at the woman who for decades was his companion.
"Either she is blinded by jealousy ... or it's a well-calculated political coup," to puncture Ms Royal's chances, ventured the chief political analyst for BFM TV, Olivier Mazerolle.