NOTE: Let us warn you that traffic coming to Bridgton can be a nightmare! Rt. 302 is a two-lane road, and is the main route between Portland, ME and No. Conway, NH. In addition, the Town of Naples had a bridge on Rt. 302 that opened several times during summer days, backing traffic up for a half mile or so. Luckily, it's been replaced with a fixed one, so delays shouldn't be an issue anymore.
Best idea is to plan to "take to the road" at unusual times. This means avoiding "rush to Maine" times, such as right after work on a Friday night, or first thing Saturday morning. Then, when leaving, avoid "checkout rush", where everyone checks out of their lodging around 10 or 11AM and immediately hits the road. Either leave really early, or take your time leaving the state and meander down the coast. You can also take advantage of transportation services, such as Airport Car Express.