Poll: Santorum's Lead Shrinking

Rick Santorum's lead over Mitt Romney appears to be shrinking in the Ohio GOP primary race. The latest poll from Quinnipiac University gives Santorum a 35-to-31 perecnt lead. That's within the poll's margin of error, and down from the 36-to-29 lead Quinnipiac reported just four days earlier. Ohio primary voters head to the polls on Tuesday.