The U.S. dollar index, where the U.S. currency is measured against other major currencies, hit a 14-month low Tuesday. Because crude is bought and sold in dollars, it essentially becomes cheaper for international investors who have flooded into energy markets despite a big surplus of oil.

Energy experts expect the government will report Thursday that crude supplies are still growing. That does not appear to be a deterrent for many investors because the dollar is so weak.

Benchmark crude for November delivery gained 88 cents to settle at $74.15 on the New York Mercantile Exchange. At one point, prices reached $74.47, just short of the $75 reached on Aug. 25, when the driving season was still in full swing.

Prices have now risen for four straight days and a barrel costs 4 percent more than it did one week ago.

Natural gas, which is not sold only in dollars, tumbled 30 cents, or 6 percent, to $4.58 per 1,000 cubic feet on Nymex.

Retail gasoline prices remain comfortably low and on Tuesday, a SpendingPulse report by MasterCard showed that American motorists consumed 2.4 percent less gas during the week ended Friday.

Those numbers could be affected by the holiday weekend, however.

MasterCard's report is based on aggregate sales activity in the MasterCard payments network, coupled with estimates for all other payment forms, including cash and check.

The average price for a gallon of regular gasoline fell less than a cent overnight to $2.478, according to auto club AAA, Wright Express and Oil Price Information Service. That's nearly 73 cents less than gas cost at this time last year.

On Tuesday, OPEC said China and other developing countries would push global oil demand up slightly next year, but added that any recovery would be "slow and weak."

The Organization of the Petroleum Exporting Countries supplies over 35 percent of the world's crude.

Iraq's oil minister said Tuesday that three international oil producers have accepted the country's terms to develop two fields and submitted revised offers, a major breakthrough for Iraq's oil industry.

The country's first postwar bidding round flopped June 30 after most oil companies rejected terms from the Iraqi government. Only one contract was awarded out of the eight oil and gas fields offered.

In other Nymex trading, heating oil rose 1.78 cents to $1.9122 a gallon, and gasoline for November delivery gained about 2 cents to $1.8195 a gallon.

In London, Brent crude rose 51 cents to $71.87 on the ICE Futures exchange.