If crude oil prices remain low as expected, the national average price for a gallon of gasoline in the United States will drift back toward $2, AAA said.

The national average retail price of $2.40 per gallon has stayed relatively unchanged for a month. The price on this date in 2014 was $3.56 per gallon. AAA said it doesn't expect the price to move above the $3 mark this year.

"There is a real hope that gas prices could drop significantly in time for the busy summer driving season," AAA spokesman Avery Ash said in a statement. "The overall outlook looks good for drivers, and with any luck we will avoid the types of problems that often lead to higher gas prices at this time of year."

In early January, the national average price for a gallon of regular unleaded gasoline was $2.05. Half of all states reported averages below the $2 mark, with Missouri on Jan. 20 posting the lowest price at $1.76 per gallon.

Crude oil prices in January drifted below the $50 per barrel mark, less than half of the June value. A modest increase in those prices, coupled with a series of refinery issues in West Coast and Midwest markets, is in part responsible for the increase in prices at the pump.

AAA said most of the seasonal refinery issues are over and, by May 1, they'll have completed the switch over to a summer-blend of gasoline, which is more expensive to make because of stricter environmental safeguards.

"Gas prices in most places are still relatively cheap and we have not seen the national average jump at the same dramatic rates that have been so common during the spring in recent years," Ash said.

The average price for a gallon of regular unleaded gas in March was $2.43 per gallon, the lowest for the month in six years. The motor club said the average U.S. household is saving more than $100 per month on gasoline because of lower prices.