I was in a line of cars waiting on the street to enter a business parking lot. The vehicle in front of me had proceeded up the incline from the street to the parking lot. I slightly raised my foot on the brake pedal when the car suddenly accelerated and hit the car in front of me. I did not remove my foot entirely from the brake until after the collision. It reminded me of having the cruise control on and the car needs more power to climb an incline or hill.