In this March 23, 2010 file photo, Marcelas Owens of Seattle, left, Rep. John Dingell, D-Mich., right, and others, look on as President Barack Obama signs the health care bill in the East Room of the White House in Washington. (AP Photo/J. Scott Applewhite, File)

Having health insurance used to hinge on where you worked and what your medical history said.

That won't matter soon, with open-access markets for subsidized coverage coming Oct. 1 under President Barack Obama's overhaul.

But there's a new wild card: where you live.

Entrenched political divisions over "Obamacare" have driven most Republican-led states to turn their backs on the biggest expansion of the net in a half century.

If you're uninsured in a state that's opposed, you may not get much help picking the right private health plan for your budget and your family's needs.

The differences will be more glaring if you're poor and your state rejected the law's Medicaid expansion. Unless state leaders reverse course, odds are you'll remain uninsured.