Debating the wisdom of the ban "would not have even been possible" just two years ago, said Lisa Murkowski, the senior Republican on the committee. But rapidly rising production of light shale oil supplies has led some to forecast a glut.
The hearing took place as new data revealed U.S. net petroleum imports at a nearly 23-year low of 5.3 million barrels per day and domestic crude production up 2.7 million barrels per day from five years ago.
Growing supplies have led to deep discounts for U.S. crude markets, boosting the profitability of U.S. refineries but reducing potential revenues for drillers.
Nymex March West Texas Intermediate, the U.S. benchmark, was up 95 cents at $98.31 per barrel on Thursday while ICE March Brent, the global benchmark, was almost $10 higher at $107.95.
"The scarcity mentality that originally led to the creation of these export restrictions no longer reflects the economic reality of the global energy marketplace that we have today," said Hamm, whose company is the biggest producer in the Bakken shale of North Dakota and Montana.
Hamm pointed out that while exports of crude are all but prohibited, the refineries that producers supply are free to sell unlimited amounts of petrol and diesel abroad. "Are we going to be their milk cows forever?" he asked.
Graeme Burnett of Delta Air Lines countered Hamm, arguing that relaxing the ban would prompt Saudi Arabia and other OPEC members to curtail oil output, keeping oil prices high and hurting American consumers "who would pay more for gasoline, more for heating oil and more for the price of an airline ticket".
Delta has $9.4 billion in annual jet fuel costs and owns an oil refinery that uses some Bakken crude.
Congress is unlikely to amend or repeal the laws that banned exports of U.S. crude to any destination but Canada, leaving decisions in the hands of the White House. President Barack Obama made no mention of crude exports in this week's State of the Union speech.
However the emerging debate could "influence the administration at the margin", Jake Dweck, an energy lawyer at Sutherland, said recently.
Ron Wyden, chairman of the Senate energy committee, said: "It is not enough to say some algorithm determines exports are good for the gross domestic product, or some other abstract concept. American families and American businesses deserve to know what exports would mean for their specific needs when they fill up at the pump or get their delivery of heating oil."
The new data from the Energy Department showed crude oil exports to Canada were 202,000 b/d in November, almost triple volumes of a year before.