Wisconsin Gov. Scott Walker opens up a big lead in Iowa

Wisconsin Gov. Scott Walker has leaped to a 10-point lead in the all-important first contest state of Iowa, in part by passing the conservative and electability test among Republican voters.

At 23 percent, he is soundly ahead of his nearest Republican opponent, Florida Sen. Marco Rubio at 13 percent, and former Florida Gov. Jeb Bush at 12 percent, according to a Public Policy Polling survey released Tuesday.