Posted: Tue, April 3 2012 at 8:10 AM,
Updated: Tue, April 3 2012 at 3:40 PM
Three states are set to hit the polls Tuesday.
Mitt Romney's expected to sweep all three primaries in Wisconsin, Maryland, and Washington D.C.
Meanwhile, his challengers Newt Gingrich and Rick Santorum aren't ready to give up.