When comparing fuels, how does natural gas fare with respect to GHG emissions for electricity?

This, according to the U.S. Environmental Protection Agency:

At the power plant, the burning of natural gas produces nitrogen oxides and carbon dioxide, but in lower quantities than burning coal or oil.

The average emissions rates in the United States from natural gas-fired generation are: 1135 lbs/MWh of carbon dioxide, 0.1 lbs/MWh of sulfur dioxide, and 1.7 lbs/MWh of nitrogen oxides. Compared to the average air emissions from coal-fired generation, natural gas produces half as much carbon dioxide, less than a third as much nitrogen oxides, and one percent as much sulfur oxides at the power plant.2 In addition, the process of extraction, treatment, and transport of the natural gas to the power plant generates additional emissions.