CHARLOTTE, N.C. (AP) -- Once a bright spot for President Barack Obama, North Carolina is more like a political migraine now.

And the ache is being felt less than four months before Democrats open their national convention in Charlotte.

The causes are plenty.

Labor unions are a core Democratic constituency, but they are up in arms.

The state's Democratic governor, Bev Perdue, isn't running for re-election in the face of poor prospects for victory.

On top of that, the state Democratic Party is in disarray over an explosive sexual harassment scandal.

Voters recently approved amending the state constitution to ban gay marriage, a position that runs counter to Obama's. And unemployment in North Carolina remains persistently high.

Party officials insist the convention will remain in Charlotte in spite of calls for moving it.