Missouri lawmakers are urging Attorney General Chris Koster to challenge the federal health care law.
The Republican-led Senate passed a resolution Wednesday asking the Democratic attorney general to either file his own lawsuit, join a suit by other attorneys general or join a suit filed by Republican Lt. Gov. Peter Kinder.
Koster's spokeswoman has said only that the office is monitoring the situation.
The Missouri legislative action comes as Republicans in charge of the U.S. House are attempting to repeal the federal health care law enacted last year by President Barack Obama. That effort is not expected to receive support in the U.S. Senate, which still is controlled by Democrats.