Tuesday morning, former Democratic Senator Bob Kerrey told 1110 KFAB that he is "not ruling out" a run for Senate in 2014.

The comment comes a day after Nebraska Senator Mike Johanns announced he will not run for re-election.

In a letter to Nebraskans (see sidebar), Johanns said it is time for this chapter in his and Stephanie's life to end. They want to spend more time focusing on family and their faith.

"To be honest with you, we are looking for a quieter life," said Senator Johanns in an interview in Sarpy County on Monday.

He'll be 64 when he finishes his term in 2015. He's spent half his life in public service as a mayor -- governor and U.S. Agriculture Secretary.

"There was no single motivating factor," he said when asked the reasons why he is not running for a second term.

Many are wondering if Governor Dave Heineman will enter the U.S. Senate Race. "My heart's in Nebraska...not Washington D.C," he said Monday afternoon.

Governor Heineman chose not to run for the open senate seat Deb Fischer won last fall. He doesn't seem to be close to changing his mind this time around. "I'll think about it -- but I don't want you to misinterpret that. I've always been very clear. I love being governor. It's always been my dream job."

Nebraska Governor Dave Heineman thanked Johanns for his service to the state.

“Senator Mike Johanns is a remarkably outstanding public official, said Johanns. "His career spans decades of dedicated service at the local, state and national levels. As a mayor, a Governor, a Cabinet Secretary, and now as a U.S. Senator, Senator Johanns has always been a leader of our state and of our nation. We are forever thankful for his commitment to serving our citizens, in particular, our farmers and ranchers, and our veterans. Sally and I are both thankful and grateful to Senator Johanns and Stephanie for their service. Nebraskans are proud of you.”