Presidential candidate Barack Obama might be running on change, but some residents of his home state do not want to shake up things too much.

A ballot proposal for a constitutional convention in Hawaii is raising fears it could have unexpected results, perhaps weakening unions or reducing the country's only recognition of native Hawaiian rights, and that its multimillion-dollar cost would come at the expense of other public programs in a tough economic time.

Hawaii is one of three states proposing a constitutional convention. In Connecticut, opponents of gay marriage hope a convention will help override a state Supreme Court decision allowing same-sex couples to wed. Illinois voters are pushing for a convention to address ethics reform, school funding and the state pension system.

Critics say constitutional conventions can have unforeseen consequences. It has been 22 years since the last time any state rewrote the basic document of state government.

In Hawaii the majority Democratic anti-convention group Hawaii Alliance, largely made up of unions and teachers, says a convention's unpredictable results and high costs are too risky in a time of budget cuts.

“;You have no idea what kind of horse-trading might go on, and some of the good things in the Constitution might go by the wayside,”; said Hawaii State Teachers Association President Roger Takabayashi.

Critics say Hawaii—unlike other states—has no crisis or issue that would form the focus of a constitutional convention.

Supporters call education, health care reform, local control and term limits issues that lawmakers have not solved but a convention could fix.

“;In this season where 'change' is the byword, it's ironic that those against a constitutional convention stand squarely against the possibility of change in our government,”; said Mark Spengler, of the group It's Time Hawaii. “;It seems to be more a campaign of fear.”;

Connecticut and Illinois ask voters whether to hold a constitutional convention every 20 years. Hawaii law requires that a constitutional convention be considered at least once a decade, but it has been 30 years since the last one.

The 1978 Hawaii convention was considered a revolutionary step for the islands because it institutionalized a right to privacy, established Hawaiian as an official language, set up the Office of Hawaiian Affairs, imposed environmental protections and set a ceiling on state spending.

Holding another constitutional convention today would jeopardize many of those provisions and potentially erode collective bargaining and pension rights, said Flo Kong Kee, executive director of the Hawaii Alliance. “;Let's not put things at risk unnecessarily,”; Kong Kee said. “;This is the wrong time, there's not a need for it, there's no compelling reason and it costs too much.”;

Republican Lt. Gov. James “;Duke”; Aiona, who has spearheaded support for the convention, put together a task force that estimated the cost of a convention at less than $10 million. Democrats asked the Legislative Reference Bureau for a competing estimate, which projected as much as $42 million.

The Hawaii Alliance has paid for ads with a $350,000 donation from the National Educational Association Ballot Measure Fund and $10,000 each from the Hawaii Government Employees Association, the Hawaii State Teachers Association and the University of Hawaii Professional Assembly.

“;The ad campaign to vote 'no' is pretty negative and scary,”; said Republican Rep. Barbara Marumoto, a 1978 convention delegate. “;They're saying, 'You're going to lose this, you're going to lose that,' and I don't think that's necessarily the case. A lot of good things could come out of this.”;