Time is running out for the supporters of the Patient Protection and Affordable Care Act to lure millions more uninsured people to the insurance exchanges. However, in a battle that's been fought largely with studies and data bases, new research just may turn the tide in PPACA's favor before the March 31 deadline for the uninsured to sign up for health coverage.

Out of the nation's 3,143 counties, researchers at the University of Minnesota have identified 116 counties where half the nation's eligible uninsured reside and 108 counties where younger uninsured Americans reside.

Dallas and Houston lead the list of PPACA targets, with Miami; Atlanta; Nashville, Tenn.; and Charlotte, N.C.; Philadelphia; Detroit; Cleveland; Indianapolis; and northern New Jersey MSA also making the list. The U of M researchers said Los Angeles County had the most uninsured folks with more than 2 million, or 5 percent of the national total.