For senate races, Obama’s visits prove mixed blessing

President Obama has had a large impact on several key Senate races ? for better and for worse.

In Pennsylvania’s Senate race, Democrat Joe Sestak relied on Obama to rally the core group of African American voters he’ll need to win the election ? and it appears to be working.

But a little further south, in West Virginia, Democratic Governor Joe Manchin is facing a tough special election bid for the late Sen. Robert Byrd’s seat ? and has been repeatedly called a “rubber stamp” for Obama.

We speak with Tony Norman, a columnist for the Pittsburgh Post-Gazette, and Emily Corio, a reporter with West Virginia Public Radio.