Obama begins Rust Belt tour, assisted by popular senators

Less than 20 months after Republicans swept almost every key gubernatorial and Senate race in the Rust Belt, three Senate Democrats head into the final four-month sprint of this years campaign as clear favorites, having weathered the worst of the tea party storm in that region.

Their good standing is good news for President Obama in states that are key building blocks to a Democratic win in the fall. Sens. Sherrod Brown (D-Ohio), Robert Casey (D-Pa.) and Debbie Stabenow (D-Mich.) have seen their public approval ratings hold steady despite continued...