RICHMOND, Va. — Michael Vick was sentenced to prison Monday for running a dogfighting operation and will stay there longer than two co-defendants, up to 23 months, because he lied about his involvement when he was supposed to be coming clean to the judge who would decide his fate.

The disgraced NFL star received a harsher sentence than the others in the federal conspiracy case because of “less than truthful” statements about killing pit bulls.

Vick said he accepted responsibility for his actions, but U.S. District Judge Henry E. Hudson said he wasn’t so sure.

“I’m not convinced you’ve fully accepted responsibility,” Hudson told Vick, who arrived in court wearing the black-and-white striped prison uniform he was issued when he voluntarily surrendered Nov. 19 to begin serving his sentence early.

Despite the early surrender, a public apology and participation in an animal sensitivity training course, Vick was denied an “acceptance of responsibility” credit that would have reduced his sentence. Federal prosecutors opposed awarding Vick the credit.

Dogs that did not perform up to expectations were killed by electrocution, hanging, drowning and other violent means by the dogfighting ring. Hudson said evidence, including statements by the co-defendants, showed Vick was more directly involved than he admitted. Hudson also mentioned that Vick had been deceptive on a polygraph test. Though that evidence was not admissible in court, the results were discussed.

“He did more than fund it,” prosecutor Michael Gill said, referring to the “Bad Newz Kennels” dogfighting operation. “He was in this thing up to his neck with the other defendants.”

The judge agreed, saying, “You were instrumental in promoting, funding and facilitating this cruel and inhumane sporting activity.”

Flanked by two defense attorneys, Vick spoke softly as he acknowledged using “poor judgment” and added, “I’m willing to deal with the consequences and accept responsibility for my actions.”

Vick apologized to the court and his family members, who along with other supporters occupied most of two rows in the packed courtroom. Before the hearing started, his brother, Marcus Vick, draped his right arm around their mother and comforted her as she wept.

“You need to apologize to the millions of young people who looked up to you,” Hudson said sternly, reminding Vick of the fans he singled out when he pleaded guilty in August.

“Yes, sir,” Vick answered.

Although there is no parole in the federal system, with time off for good behavior Vick could be released in the summer of 2009.

On its Web site Monday, the Atlanta Journal-Constitution estimated that Vick has incurred financial losses of $142 million, including $71 million in Falcons salary, $50 million in endorsement income and nearly $20 million in previously paid bonuses.

Federal sentencing guidelines called for a term of 18 months to two years. While prosecutors asked for a sentence on the high end, defense attorney Lawrence Woodward asked for leniency, noting his client’s previously clean record despite growing up in a rough area in Newport News.

But in addition to initially lying about his role in killing dogs, Vick tested positive for marijuana use in violation of the terms set for his release — then gave conflicting accounts about when he used the drug, Hudson noted. Along with the prison term, Vick was fined $5,000 and will serve three years’ probation after his release.