ATLANTA - Gov. Sonny Perdue on Wednesday asked the state attorney general to join seven of his colleagues from other states in investigating a political deal struck to pass a federal health care reform bill.

In a letter, Perdue, a Republican, asked Thurbert Baker, a Democrat, to "explore the availability of any legal challenges that Georgia could pursue to oppose this unconscionable scenario."

The state's two U.S. senators - Saxby Chambliss and Johnny Isakson, both Republicans - also urged Baker to look into the constitutionality of special exemptions in health care legislation moving in the Democratic-controlled U.S. Senate.

Perdue has said the bill, which the Senate is expected to vote on today, would heap additional Medicaid costs on states such as Georgia.

South Carolina Attorney General Henry McMaster said Tuesday that he and his counterparts in Alabama, Colorado, Michigan, North Dakota, Texas and Washington state - all Republicans - were jointly taking a look at the deal they've dubbed the "Nebraska compromise."

The provision, which permanently exempts Nebraska from paying Medicaid costs that other states must pay, helped win Nebraska Sen. Ben Nelson's vote on the massive health care bill.

Baker dismissed calls for a probe, saying it's premature because the legislation has yet to even pass.

"At this time there's absolutely nothing to investigate or probe or challenge," Baker said, "No one can challenge the legality of a bill before it becomes law."

Baker is seeking the Democratic nomination for governor.

Perdue has been increasingly vocal in his opposition to health care reform bills moving in Washington.

On Monday, Perdue took the unusual step of releasing a statement blasting the legislation and the political jockeying taking place in Washington to gain the necessary support.

"This bill places an unsustainable burden on the backs of Georgia's taxpayers, and will lead to either higher state taxes or massive cuts to basic state services in years to come," Perdue said.