One of the highest immediate political priorities for Senate Majority Leader Harry Reid (D-Nev.) and Senate Democratic political guru Charles Schumer (N.Y.) is to persuade veteran colleagues not to retire in 2014.
Democratic sources identify four senators as most likely to retire: Sens. Jay Rockefeller (D-W.Va.), Tim Johnson (D-S.D.), Frank Lautenberg (D-N.J.) and Tom Harkin (D-Iowa).
Another possible veteran retirement is Senate Armed Services Committee Chairman Carl Levin (D-Mich.), who has yet to announce his decision. But Democratic aides expect him to run again.
Democrats would have a tough time defending their seats in West Virginia and South Dakota without incumbents running. Iowa, a blue-leaning state that gave President Obama a six-point victory over Mitt Romney, is a competitive race that slightly favors Democrats and New Jersey is a safe bet to stay in their column. Michigan resembles Iowa in that it leans Democratic but a strong Republican candidate could capture the seat if Levin leaves.
Rockefeller is seen as the most likely to step down from the Senate at the end of 2014. He reported only $704,000 in his campaign account at the end of September and a high-profile break with the coal industry — a powerful player in West Virginia — was interpreted as a sign he would not run.