The French left-wing candidate, Hamon, has definitely lost the first round in the French election. It looks likely that Macron (centre left) and Le Pen (far right) will go through to the second round. Hamon has thrown his support behind Macron.
Hamon has just said "We have to defeat the far right, an enemy of the Republic, by voting Macron even if he is not a man of the left".
That's why people support second best, rather than squabbling, which lets in the "enemy".
There are parallels between the left and right of the Labour Party.