RICHMOND, Va. — A quickly done overnight opinion by conservative attorney general Ken Cuccinelli on a Medicaid expansion compromise threatens to derail transportation funding reform legislation.

Votes on both issues were expected Saturday on the last day of the legislative session.

At the request of Republican Del. Ben Cline, Cuccinelli penned an opinion Friday night that says a proposed legislative panel to oversee reforms necessary to expand Medicaid to 400,000 uninsured Virginians near the poverty level is unconstitutional.

That would void a letter from Gov. Bob McDonnell to Senate Democrats who had promised to block passage of the transportation package without written assurance from McDonnell affirming the panel.

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