The Credit Agricole sprinter took the honours after a 191km stage from La Roche-sur-Yon to Riaillé, beating Gerolsteiner's Robert Förster in the bunch sprint.
Agritubel's Anthony Ravard and Française des Jeux rider Lilian Jégou had enlivened the opening stage of the 2.1 category race by gaining a ten minute advantage on the peloton.
But the sprinters' teams drove the chase and the escapees were reeled in inside the final 15km, setting up Furlan for his second victory of the season.
Cummings and Roche ready to roar
The four-day race, which features eight ProTour teams, continues on Wednesday with a road stage followed by a time trial.
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