Who is actually leaving a larger carbon footprint, the person driving with 5 other people in a large SUV, or a single person driving a sports coup alone?

If a person had a large SUV that seats 8 and is traveling on a trip 70 miles up and back with 5 other people, making it 6 total in the vehicle, would they make a larger or smaller carbon footprint than a single driver in a sports coup taking a trip 25 miles up and back?