History. 2 of 4: the parties in the talks had one candidate in the first round in 2012 (left) and 2017 (right), and two or more in 2017 (left) and 2022 (left). For the left in 2027 the answer is not known yet.
Hunch. On 8 November Gabriel Attal said it made no sense to step aside for Edouard Philippe, a man he says polls put third or even fourth.
The one-candidate market resolves on the list of first-round candidates that the Conseil constitutionnel publishes before 18 April 2027: YES if exactly one candidate on it is a member of, or officially backed by, Les Républicains, Renaissance, Horizons or Nouvelle Énergie. Two or more such candidates, or none, resolve NO, and France 24 and Politico Europe are the backups.
We looked for cases where parties of one French camp, the left or the centre and right, had a joint primary on the table before a presidential election. We found five such times since 2011, four on the left and one on the centre and right. The Socialist vote of 2011 was the first open vote of its kind in modern France. (The Guardian; The Guardian; BBC; Politico Europe; Le Monde)