LOS ANGELES – It’s more night than morning when Jimmy Pastor pulls his blocky 1961 Chevy milk truck out of the Santa Ana, Calif., parking lot for his delivery run, his white uniform starched, his red-and-white cap snug on his head.

He’s jolted awake when he pulls into a Chevron station nearby and sees that gas prices have leaped 15 cents overnight, to $4.29 a gallon.

“Just driving to work in the morning scares me,” said Pastor, 54, who has been driving a milk truck in Southern California for 32 years and owns his own business. “This economy cannot absorb $5-a-gallon gas.”

Motorists everywhere are getting hammered by the cost of gas, which jumped to an average of $3.72 a gallon nationwide last week, up 13 cents from the week before and 34 cents from a year earlier.

The toll is especially heavy on the small business owners who depend on their cars and trucks to bring goods and services to consumers. These enterprises — carpet cleaners, food truck drivers, cabbies, gardeners, traveling massage therapists, exterminators, plumbers and the like — say their profit or loss is inextricably linked to the price of gas.

They can’t easily raise their prices or impose fuel surcharges because their customers, like them, are feeling the pinch of higher prices at the pump. And unlike airlines or big delivery companies, they aren’t big enough to hedge fuel purchases in the futures market.

“It’s really the small-time delivery guys who are almost immediately affected by high gas prices,” said Bob van der Valk, a petroleum industry analyst. “The flower delivery guy, cab drivers, people who live from hand to mouth, end up having to take it out of their grocery money or rent to pay for gasoline.”

Justeen Ward, owner of A Class Act, a singing telegram and clown company in Van Nuys, Calif., says she’s forced to drive farther than ever before to drum up business, because consumers are so hesitant to spend. She doesn’t add a gas surcharge, so days such as last Saturday really hurt. First she drove to Orange, Calif., to work as a clown, then 20 miles to Aliso Viejo, Calif., to deliver a telegram as a singing bag lady.

“I thought things were getting a little better, and then they just crashed,” said Ward, who said it costs $70 to fill up her 1997 Lexus. “Gas prices and people’s employment pictures really affect us.”

Rising gas prices have also boosted wholesale prices of food and other commodities, dealing a double whammy to mobile food businesses.

“Our whole culture is based on affordable, approachable, cheap food,” said chef Roy Choi of Los Angeles’ mobile Kogi food trucks. He’s now paying $4 a pound for short ribs, up from less than $3; and a crate of green onions has shot up to $16 from $11. “That formula has worked for a long time, but the gas has affected the price of the food we buy.”

Pastor fields about 12 to 15 trucks on any given day. His company, Wow Delivery, spends about $12,500 a month on fuel.

To cover rising costs, he has started twice-weekly deliveries and added eggs, produce and tamales to his offerings. The changes have helped his company add about 1,000 customers in the past six months for a total of about 5,400 in Los Angeles and Orange County coastal communities such as Santa Monica, Redondo Beach and San Clemente.

But customers started cutting back in recent weeks, asking for one gallon of milk instead of two. Last week, he laid off two employees.

“Things were getting better, but now, all of a sudden, boom. I either have to pass the costs on to my customers or close the doors,” he said.

A high school dropout, Pastor said his frustration is compounded by a seeming lack of concern by national leaders over rising fuel costs.

“I’m not a tea party or coffee guy, or whatever those guys are. I’m a working guy,” he said. “I got no one worrying about me, and there’s a million guys out there like me. Little guys. Little businesspeople.”

Small businesses such as Pastor’s, however, are a linchpin in the economy overall. Analysts say businesses with fewer than 500 employees account for more than half of all new jobs created, and are generally the first to pick up hiring after an economic downturn.

“Coming out of recession, small businesses do hire the vast majority of people,” said Chris Christopher, senior principal economist at IHS Global Insight. “But this time around, they’re just struggling too much.”

Some say the answer to rising gas prices is to convert to electric and alternative-fuel vehicles. But that’s an expensive option for small businesses.

Pastor said he looked into adding electric vehicles to his fleet but said he would need to spend about $100,000 for a truck that met his needs.

For now, he’ll continue to drive through the quiet streets at 3 a.m., stopping in front of low-slung houses with white picket fences to deliver a gallon of milk from a 1961 vintage truck from which he said he used to make deliveries to Richard Nixon’s home in San Clemente.

His is the only car on the streets this early, though in the past he’s seen mountain lions, skunks in love and, in the 1970s, other milk delivery competitors, sometimes five to a street.

When he finishes for the morning, there’s not even a hint of dawn in the sky, unless one counts the bright neon lights of the Chevron station where he passes by once more, scoffing at the reminder of his troubles.

“They say it’s not how many times you fall, it’s how many times you get up,” Pastor said. “Well, it keeps getting harder to get up.”