The Affordable Care Act (ACA) marketplace opens up tomorrow, but New Jersey residents are still divided on what Obamacare will mean for them.

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Most claim they understand the health care reforms, but a new joint survey by Monmouth University and the New Jersey Health care Quality Institute reveals Garden Staters know less about the ACA than the rest of the nation.

Just under half (45 percent) of New Jersey residents have a favorable opinion of Obamacare, while 40 percent have an unfavorable view and 16 percent have no opinion. About half (49 percent) thinks the quality of their own health care will not be affected by implementation of the ACA, although 30 percent think it will get worse and just 13 percent think it will get better.

There are more concerns about Obamacare's impact on health care costs than on quality. Better than 4-in-10 New Jerseyans (42 percent) predict their own costs will get worse under the ACA, compared to 37 percent who say their costs will stay about the same, and just 14 percent who say they will improve.

"Right now we've got a lot of people on both sides saying costs are going to go down, costs are going to go up, you're not going to have adequate coverage, you're going to have plenty of coverage," says Dave Knowlton, President and CEO of the New Jersey Health Care Quality Institute. "A people go and check out the exchange and start to see what it means to them we're going to get some feel for what they think this means for them."

Most New Jerseyans feel they understand the health care reforms either very (18 percent) or somewhat (49 percent) well. Only 3-in-10 say they understand the ACA not too well (19 percent) or not well at all (12 percent). Those beliefs may be misleading because just 1-in-3 New Jerseyans have heard a lot (11 percent) or some (23 percent) regarding the new health care exchanges. Another 31 percent have heard only a little and 33 percent have heard nothing at all.

Obamacare has an individual mandate and New Jersey is significantly less informed than the nation when it comes to that issue.

Just over half (56 percent) of the state is aware that the new law requires nearly all Americans to have health insurance by next year or pay a fine. Another 24 percent wrongly say there is no such mandate in the law, and 21 percent admit they do not know if such a provision exists. A March poll the Kaiser Health Tracking Survey found that 74 percent of Americans said the ACA requires individuals to purchase health coverage or pay a fine.

Just over 1-in-10 (11 percent) New Jersey adults report that they don't have health care coverage right now. Among this group 62 percent say will probably obtain health coverage for 2014 after learning of the individual mandate. Another 24 percent say they will remain uninsured despite the mandate's fines, while 13 percent are uncertain about what they will do.