DES MOINES, Iowa (AP) — Once largely united against the Obama administration's new health care overhaul, a growing number of Republican governors are now buying into parts of the system.

This week, Michigan's Rick Snyder became the sixth GOP governor to support expanding his state's health insurance program to cover more low-income residents.

Snyder concluded that the state's higher Medicaid cost would be outweighed by the large amount of federal money Michigan would receive.  Expanding Medicaid is optional for states, and most Republican governors have not agreed to do so.  Many fear the federal government could later renege on covering its share of the costs.

The administration is pushing the states to participate so that most low-income people will have health coverage when the new system begins next year.