Following a post-Bridgegate nosedive, Gov. Chris Christie's job approval numbers have held firm since February, but a new poll reveals a significant amount of New Jersey residents don't believe the governor has come clean about his involvement in the decision to close access lanes to the George Washington Bridge last September.

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Among all New Jersey residents in the Monmouth University-Asbury Park Press poll, 50 percent approve of the job Christie is doing while 42 percent disapprove. Those figures are virtually unchanged for registered voters, 49 to 43 percent.

"It looks like he took a big hit in January right after Bridgegate broke, but those numbers stabilized within four weeks and so since February until now, his numbers have been pretty much steady," said Patrick Murray, director of the Monmouth University Polling Institute. "His numbers on his personal rating, how people feel about Chris Christie the man, have changed a little bit: 45 percent have a favorable opinion of him -- that's up five points -- (and) 38 percent have an unfavorable opinion. That's up three points."

There is no evidence that directly links Christie to the Bridgegate scandal, but the survey shows people don't necessarily believe the entire story has been told.

"The Bridgegate issue is interesting because the governor's job approval ratings haven't moved, but many people still don't believe that he had nothing to do with it," Murray said. "In fact, 46 percent say that the governor was personally involved in the decision to close the lanes, despite the fact that the governor says he wasn't."

A majority (55 percent) thinks Christie is more interested in his own political future versus 32 percent who say he is more concerned with governing the state of New Jersey.

Some top Democrats think the lanes were closed to punish Fort Lee's mayor for refusing to endorse Christie's re-election. The Select Committee on Investigation is probing the scandal and has scheduled a July 8 meeting to take more testimony.

The poll revealed many Garden State residents are not impressed with the SCI:

58 percent of New Jerseyans say the committee is really just interested in going after the governor," Murray said. "Only 26 percent say that the committee investigating the issue is primarily about learning the facts of the case."

The governor has decided to slash the Fiscal Year 2015 pension payment by almost $1.6 billion. On Monday, he vetoed a tax increase on millionaires that would have ensured the full payment. The poll finds that 62 percent of respondents believe the state's pension costs are out of control, but only 35 percent blame Christie. Almost half (49 percent) said they have no opinion of the governor's decision to cut the FY '15 pension payment.

Exactly two-thirds of poll respondents said they support a millionaires' tax increase. Christie also vetoed a tax increase on corporations. Only 4 in 10 thought hiking the Corporation Business Tax rate was a good idea to help fund the pension system.