WASHINGTON – In a report with political significance, the Labor Department said Friday that companies added 96,000 jobs to their payrolls last month, far short of the 150,000 increase that had been widely expected.

Economists called the modest rise disappointing and said the slower hiring pace was likely caused by corporate caution in the wake of higher energy prices, surging health-care costs and concerns about terrorism.

The report gave Democratic presidential contender John Kerry new ammunition to use against President Bush as the presidential campaign heads into the home stretch.

“The verdict is in,” Kerry said. “With 1.6 million private-sector jobs lost during his term, President Bush will be the first president in 72 years to face the electorate with an economy that has lost jobs during his watch.”

But 1.1 million government jobs have been created during Bush’s presidency, partly offsetting the impact from the private-sector losses.

Stressing the positive side of the final jobs report before the Nov. 2 election, Treasury Secretary John Snow noted that the unemployment rate remained at 5.4 percent, which is low by historical standards. He also said the report showed “a steady creation of jobs fueled by the pro-growth policies and strong economic leadership of President Bush.”

There is no economic statistic more important than the closely watched monthly employment figure. Although economic growth appears to have picked up in recent weeks, employment once again appears to be lagging as companies seek to grow with better efficiencies rather than increasing work forces.

Bill Cheney, chief economist at MFC Global Investment Management in Boston, said he is concerned about the future labor market because not enough jobs are being created to keep up with population growth. It would take at least 150,000 new jobs a month to make a dent in the unemployment rate.

He said creating 96,000 jobs “is a lot like a bloop single in the ninth inning with one out and the team down four runs. It may keep hope alive, but it won’t win the game.”

The Labor Department also issued a revised estimate saying 236,000 payroll jobs had been created in the 12 months between March 2003 and March 2004, an upward revision and a plus for the administration.

But Republicans had hoped that this newly re-estimated figure for payroll jobs, called “benchmarking,” would have produced an even higher total and given Bush bragging rights on the economy heading into Friday night’s presidential debate.

Snow said the economy has produced 1.9 million jobs in the past year. Democrats said that in Bush’s term, a total of 821,000 payroll jobs have been lost.

In fact, if the 236,000 revised estimate is counted – and economists said it should be – then 585,000 jobs have been lost since Bush assumed the presidency.

The Labor Department said the fact that four hurricanes struck the United States during August and September probably held down employment growth “but not enough to change materially” last month’s jobs numbers.

Some economists said they suspected that employers would have added 40,000 more jobs if it weren’t for the storms, but they stressed that this was only guesswork.

During the past three months, the government said, payroll employment has risen an average 103,000 per month. But the August boost of 144,000 was revised downward to 128,000.

While politicians on both sides argued about the meaning of the report, a number of private economists said it showed a weaker job market than they had expected. Some said it might cause the Federal Reserve to rethink its plan to raise interest rates gradually.

Carl Tannenbaum, economist at LaSalle Bank in Chicago, said he had expected better numbers based on his reading of several private surveys and instead found the jobs picture last month “slightly glum.”

He said analysts had been expecting that income growth would begin to propel the economy and job increases, as the impact of tax cuts and home refinancings came to an end. The job numbers may indicate the recovery is facing greater risk, Tannenbaum said.

“A structural change is occurring in the labor market, partly because companies are scared of commitment, partly because of terrorism, oil prices and other uncertainties,” said David Wyss, chief economist for Standard & Poor’s.

Rather than taking on more workers and taking on costly fringe benefits, he said, companies are shifting more into using “just-in-time” contract and temporary workers. “This is the age of the virtual company,” he said.