SPRINGFIELD - Republican Judy Baar Topinka's support of opening a casino in Chicago is not sitting well with some members of her own party.

The GOP gubernatorial candidate's plan, unveiled Wednesday, goes against long-held Republican opposition to the expansion of gambling in Illinois.

Reaction among lawmakers who will have to vote for it if Topinka beats Democratic Gov. Rod Blagojevich in November was tepid.

"I have traditionally voted against expansion of gambling in the past," said state Sen. Dave Luechtefeld, an Okawville Republican.

"I probably wouldn't vote for it," added state Sen. John Jones, R-Mount Vernon.

State Rep. Bob Pritchard, R-Hinckley, said he'd study the proposal, but, he said, "I'm not excited about the expansion of gambling."

Topinka says the Chicago casino would raise an estimated $5 billion over four years. The money would bankroll her plan to boost spending on schools and state construction projects, as well as to freeze school property taxes for two years.

State Sen. Bill Brady, R-Bloomington, who challenged Topinka for the GOP nomination in March, gave Topinka credit for outlining a way to pay for her programs.

But, he said, "I am concerned about an expansion of gambling. I've never supported it."

Gambling revenue has traditionally been used to plug budget holes without raising taxes. Recent efforts to add casinos to the existing nine gambling outlets, however, have stalled in the General Assembly.

In 2005, Republican leaders in the House and Senate said their members were opposed to adding slot machines at Illinois horse tracks.

State Sen. Dan Rutherford, R-Chenoa, who is now running for secretary of state on the same ticket as Topinka, said in 2005 that gambling is "an inappropriate way to feed the jabberwocky of a hungry government."

Topinka, currently the state treasurer, acknowledged that she has not been a proponent of gaming in the past.

But she maintained her proposal would not be an expansion of gambling in Illinois because the Chicago casino would be taking the spot of the state's unused casino license. That license was previously held by the Emerald Casino, which intended to locate a gambling boat in the Chicago suburb of Rosemont.

The Illinois Gaming Board voted unanimously in December to revoke Emerald's gambling license, calling the casino a "stain on the gaming industry" where top company officials lied to regulators and let people with alleged ties to organized crime become investors.

Topinka's proposal calls for adding an additional 1,800 gaming positions at each of Illinois' nine riverboats - allowing each boat to have a total of 3,000 spots, if they choose. The Chicago casino would have 3,000 gaming positions.

The process of awarding a Chicago license would be through an open bidding process, Topinka said, and she did not envision the casino being located in a neighborhood, at either of the airports or Northerly Island, formerly home of Meigs Field.

Topinka said she had discussed her proposal with Chicago Mayor Richard M. Daley and he reacted "reasonably well," but wanted to look at the plan further.

Daley has previously said he would want any casino in Chicago to be owned by the city. Topinka said she does not support any government entity owning a gambling site.

- The Associated Press contributed to this story.