Mitt Romney's father, George Romney, paid an effective tax rate of nearly 37% in 1967.

CNN: Mitt Romney vs. stubborn facts

If the strategy worked, Mitt Romney and George W. Bush could both take credit for reforming health care by using market-based ideas and without raising taxes.

NEWYORKER: Romney��s Dilemma

However, the Obama re-election team often points to Romney's father, the late George Romney, who released 12 years of tax returns when he ran for president in 1968.

CNN: Obama, Romney ratchet up back and forth over outsourcing