SPRINGFIELD - Advocates hoping to stop Gov. Rod Blagojevich from closing state parks and historic sites are looking to the federal government for some help.

Supporters of keeping the two dozen sites open in the face of the governor's budget cuts are studying whether the use of federal dollars at the facilities could derail the plan.

At the Hennepin Canal Parkway, for example, advocates say more than $15 million in federal funds were used to help improve the facilities. Under their interpretation of federal rules, that money would have to be repaid if the governor goes through with the closing.

At Wolf Creek State Park, federal officials are investigating whether the state's partnership with the U.S. Army Corps of Engineers could play a role in whether the governor moves forward with his planned closure of the Lake Shelbyville facility.

"We're probing about to see what we can do there," said Phil Bloomer, spokesman for Republican U.S. Rep. Tim Johnson of Urbana.

The Blagojevich administration is aware of the situation.

"To my knowledge no determination for any site has been made, though we are aware of all the variables at each site and continue to work with our federal partners to address any potential scenario," said Illinois Department of Natural Resources spokesman Chris McCloud.