By 'Centrist' they mean 'Not the furthest Left candidate.' He was in Hollande's administration, and is pretty much totally a Socialist. He is, unfortunately, likely to win because the total of all the Leftie factions together definitely outnumbers Le Pen, who already represents a consolidated Right-wing coalition, and the Left is likely to coalesce around Macron now that the herd has been culled. He seems like a White Obozo - photogenic unknown quantity, a blank screen upon which the voter can project his or her own variation of Leftist ideology.