Gas heat is less expensive than electric per BTU of heat. Even though natural gas prices in North America are low right now, utilities can produce electricity from it at 25-30% thermodynamic efficiency. This means that you will get 3-4 times more heat for each unit of gas you burn. Although some heat is lost through the flue, the economics favor gas. Although electric heaters tend to be more affordable, I don’t believe this offsets the higher fuel prices.
Only use electric heat where gas is not available, or when localized heating is required (e.g. heating one room) or in homes that have very little ventilation.