Democrats believe Iowa Gov. Terry E. Branstad is vulnerable, but it will be almost a year before they know who will be their nominee to take on the Republican.

State Sen. Jack Hatch and former state Rep. Bob Krause are already running, but they will have company soon. State Rep. Tyler Olson, the former Iowa Democratic Party chairman, is expected to join the race. Physician and businesswoman Andy McGuire and others could get into the race as well before the March filing deadline.

Meanwhile, Branstad is preparing to run for a sixth term, according to the Des Moines Register (via Iowa Politics in Stereo). He served four terms, starting in 1982, and then was elected again in 2010, when he defeated then-Gov. Chet Culver, a Democrat.

Maybe one of the Democratic candidates catches fire or Branstad implodes. But for now, we’re moving the race from Lean Republican to Republican Favored in the Rothenberg Political Report/Roll Call ratings.