Monaco are five points clear of Marseille who play Nantes on Sunday.
Bordeaux had won four of their last five games before the trip to the Stade Louis II on Friday night. And they showed that confidence in the opening exchanges.
They took the lead with through Valentin Vada. The 21-year-old Argentine ghosted into the box to thump a first time strike into the top corner.
But on the stroke of half-time, Stevan Jovetic's levelled for the hosts. Lopes then sealed the three points in the 69th minute.
Lopes had scored five times in Monaco's last six league games, including a brace in last week's 3-3 draw at Toulouse. "He is one of those players to show their capacity to succeed, so I congratulate him," said Monaco coach Leonardo Jardim.
"He has made the most of the eight months since he returned from his loan period at Lille."