Former U.S. attorney general and Missouri governor John Ashcroft on Monday added his name to Mitt Romney's endorsers.

"As a conservative who served as governor of Missouri during the Reagan revolution, I admire Mitt's record of fiscal responsibility, lower taxes and defense of traditional values in a politically difficult state for a Republican," Ashcroft said of Romney.

Ashcroft joins House Majority Leader Eric Cantor of Virginia and Sen. Tom Coburn of Oklahoma as leading conservatives who are now backing Romney.

Meanwhile, three polls released Monday show Romney in a statistical tie for the lead in Ohio. A week ago, Romney was trailing former senator Rick Santorum of Pennsylvania there.