The reason gas prices you pay at the pump fluctuate so frequently is that the price for gas is dependent on what the retailers pay for the gas. The retailers pay gas companies. Gas companies charge for gas depending on what the current price is for crude oil. This is heavily dependent on supply and demand for oil.
Politics can impact oil prices if countries needing oil and countries supplying oil are at odds with each other. Instability in a country supplying oil can also impact prices if it becomes harder to extract or export the oil from the country.