Cain has proposed eliminating the income tax for a family of four below the poverty line, which is now $22,350. Because this family exceeds the poverty line, its income tax bill would be $2,655. If Cain exempted all income below the poverty line, that bill would change to $644.
What is difficult to determine with as much precision is how Cain's national sales tax and proposed business tax, which doesn't allow a deduction for wages, would affect this family.
"It's a campaign platform without really being a true tax policy plan," Pickering said. "There's so many things that we don't really know how to make the assumptions about."
Obama Plan
In contrast with the Republican plans, Obama would focus much of his tax policy on raising taxes for the highest earners. He proposes to increase the top marginal rate to 39.6 percent, keep taxes from the health-care law, cap deductions at 28 percent and allow the top capital gains rate to rise to 20 percent.
For the wealthy family, those proposals combine for a 22 percent tax increase and a total tax bill of $302,947, or more than twice what Cain, Perry or Huntsman is proposing.
For the other three families in the study, Obama would continue current tax policy and leave their tax bills unchanged.