Republican challenger Christopher J. Christie posted a 10-point lead yesterday over Democratic Gov. Corzine in the first independent poll of the general election, prompting a wave of attacks against Christie by prominent New Jersey Democrats.

In Washington, Sen. Robert Menendez and Rep. Bill Pascrell criticized Christie for saying he would not take $17.5 billion in federal stimulus money if rules could hobble his independence as a governor.

And word got out that a congressional subcommittee had invited Christie, a former U.S. attorney, to testify this month about awarding lucrative contracts to his old boss, former Attorney General John Ashcroft, and other former prosecutors.

Democrats have characterized the agreements, under which outsiders are hired to monitor corporations accused of criminal acts, as no-bid, pay-to-play deals, an allegation Christie vehemently denies.

His campaign manager, Bill Stepien, said yesterday that Christie would testify before the subcommittee only if it was trying to improve government contracting and was not engaged in political gamesmanship.

Corzine is slowly releasing his personal fortune to drive his campaign, a factor that many observers say will change the race's dynamics. On Friday, he began running a pair of ads on cable TV aimed at shoring up Democratic support.

A political group partly funded by the Democratic Governors Association is expected soon to resume ads attacking Christie.

For now, though, Corzine is running behind the Republican nominee.

In a Quinnipiac University poll of 1,338 voters conducted between June 3 and Monday, Christie led Corzine, 50 percent to 40 percent. The poll's margin of error was plus or minus 3 percentage points.

Results also underscored Corzine's slump in popularity. Fifty-six percent of respondents said they disapproved of the job he was doing. Most also said they found Corzine cold and businesslike and unable to understand their problems.

Clay Richards, the poll's assistant director, said he asks the same warm-and-fuzzy question about New York Mayor Michael Bloomberg and gets similar answers. But although New Yorkers don't want to cuddle up to Bloomberg, respondents there think he is doing a good job, Richards said.

Unlike voters in Pennsylvania and Connecticut, voters in New Jersey blame the lousy economy on their governor, he said.

He added that New Jersey voters were angry that Corzine had curtailed property-tax rebates this year.

Christie has attacked Corzine as failing to feel voters' pain and implied that was because the governor is a wealthy man who made his fortune on Wall Street.

Corzine, though, has room for improvement, Richards said. If he woos more Democrats and independent voters, "he's got room for a comeback," he said.

Corzine campaign spokesman Sean Darcy said voters would know by Nov. 3 that "for three years the governor has been focused on restoring fiscal responsibility and getting the state's house in order." Darcy said the campaign would talk about how the governor had cut state spending and held the line on property taxes, and how New Jersey was the first state to pass a comprehensive economic-recovery plan.

Though Christie has been ahead of Corzine in Quinnipiac polls since August, Montclair State University political scientist Brigid Harrison noted that Christie was relatively unknown among voters. That gives Corzine a chance to define him.

"Jon Corzine can make some hay by informing their opinion in a negative way," she said. "Call me cynical, but I certainly think that it is in the governor's best interest to have Mr. Christie's name brought up in any negative connotation possible."

And yesterday it was.

Menendez and Pascrell chided Christie for saying during the Republican primary that he would turn down federal aid with strings attached.

Menendez said the strings on stimulus funding for unemployment benefits, education aid, police hires, and public-works projects were oversight requirements.

"How can you be fiscally responsible without requirements?" he asked. "You can't rail about fiscal responsibility and say you want $17 billion and don't want strings attached."

Pascrell said Christie should tell the police, the unemployed, and students that he didn't want the money.

"Look in their eyes and tell them we don't need it," Pascrell said. "We're helping ourselves get back on our feet."

Christie's campaign said the Democratic attacks, which began in the GOP primary, had been unrelenting.

"Each week it seems there is a new crop of political caddies rolled out to attack Chris," said Stepien, adding that Democrats had spent about $2 million attacking Christie. "I'm sure it's going to get worse."

He said the Quinnipiac poll showed "people are looking at unemployment rates, tax bills, and at things that really matter."

Contact staff writer Cynthia Burton at 856-779-3858 or cburton@phillynews.com.