Reims led at halftime after Floyd Ayite's deflected 25-yard free kick and Mads Albaek's strike.
Marseille, which was booed off the pitch at the interval, reduced the deficit 12 minutes after the break following a run and shot from Florian Thauvin for his first goal since his controversial move from Lille.
Souleymane Diawara also had a goal for Marseille ruled out for offside on the half hour.
Marseille is provisionally sixth, seven points behind leader Paris Saint-Germain, which visits Saint Etienne on Sunday.
Promoted Guingamp moved above Marseille on goal difference following its fourth win in five matches, after two late goals saw it come from behind to beat Ajaccio, which fell to its third successive defeat.
Ajaccio took the lead three minutes from halftime when Benjamin Andre's header was dropped by Guingamp goalkeeper N'Dy Assembe into the back of the net.
However, Claudio Beauvue leveled with a bicycle kick four minutes from time and Moustapha Diallo headed in the winner at the death.
Nice is level on points after losing 1-0 at Bastia, in a match in which both sides were reduced to 10 men.
Sebastien Squillaci put Bastia in front in the 36th minute, heading a corner into the bottom left of goal after he was left unmarked at the far post.
Bastia striker Gianni Bruno was shown a straight red card 13 minutes into the second half for a high tackle on Nemanja Pejcinovic, and Mahamane Traore was also sent off four minutes from time for a second booking.
Rennes is a point further back after goalkeeping howlers as it beat Toulouse 5-0 and earned its first victory in five matches.
Romain Alessandrini opened the scoring in the 25th minute, pouncing on a loose ball after Toulouse goalkeeper Ali Ahamada misjudged Jonathan Pitroipa's effort.
Ahamada was again at fault nine minutes later as he failed to deal with Alessandrini's crossed free kick and Tiemoue Bakayoko headed into an empty net.
The Toulouse goalkeeper then inexplicably handled the ball outside his area just before halftime and Foued Kadir fired in the resulting free kick.
Nelson Oliveira struck twice in the second half to complete Toulouse's humiliation.
Rock-bottom Valenciennes is in further trouble after conceding a late goal in a 1-0 loss at home to Evian left it five points adrift of safety.
Modou Sougou scored the only goal of the game eight minutes from time. Valenciennes has gone 10 games without a win.
Elsewhere, Lorient snapped a run of four straight defeats with a 2-0 win over fellow struggler Sochaux.
Vincent Aboubakar volleyed in Bryan Pele's cross from the middle of the penalty area in the 17th minute and turned provider 10 minutes into the second half, setting up Yann Jouffre. Cedric Bakambu netted a consolation for Sochaux in the final minute.