NEW YORK — Gasoline prices paused this week in their march toward $4 per gallon.

After 39 straight days of increases, prices fell nearly a penny from Tuesday to Thursday and held steady on Friday at $3.758 per gallon. The lull won’t last long.

Prices dipped as suppliers conducted the equivalent of a spring clearance. They are discounting winter gasoline blends to make room for different blends that are required for summer driving, said Tom Kloza, chief analyst at the Oil Price Information Service.

Prices will start to rise again once the winter gasoline has been sold off. They have to, Kloza said, since summer gasoline costs more to produce because it contains smog-fighting additives. The switch to summer gas also creates a temporary dip in supplies as wholesalers sell off winter stocks, and that can force prices higher as well.

OPIS forecasts that average gasoline prices will rise as high as $4.25 per gallon across the country by late April. That would top the record high of $4.11 set in July 2008 and keep gasoline center stage during this year’s presidential election. Republicans have blamed President Barack Obama for the high prices, while Obama has dismissed the criticism as election-year politics. Obama has asked his attorney general to look into the possibility that commodity speculators are driving prices higher.

The average price for gasoline is already more than $4 per gallon in California, Alaska and Hawaii. It’s nearly there in Connecticut, Illinois, New York, Oregon and Washington.

The price of gasoline has mostly followed the rising price of its main component, crude oil. Oil, which is traded around the world, has become more expensive this year on fears of supply shortages in the Persian Gulf due to an international standoff over Iran’s nuclear program.

Oil prices continued to rise Friday after the U.S. said its economy added 227,000 jobs in February. The U.S., the world’s largest oil consumer, has seen the strongest three months of job growth since the Great Recession. An improving economy is likely to lead to more demand for oil.

Benchmark West Texas Intermediate crude, which is used to price much of the oil produced in the U.S., rose by 82 cents to end the day at $107.40 per barrel in New York. Brent crude, which prices oil imported by U.S. refineries, rose by 54 cents to finish at $125.98 per barrel in London.

Natural gas futures rose by 5 cents to end at $2.32 per 1,000 cubic feet. Earlier in the week, natural gas dropped to the lowest level in 10 years following a relatively warm winter and a boom in U.S. production.

In other energy trading, heating oil fell by less than a cent to finish at $3.26 per gallon and gasoline futures rose 2 cents to end at $3.33 per gallon.