Alaska is one of seven states which have a Democratic-held Senate seat up this year and which voted for Mitt Romney in 2012. Nate Silver of 538 and Chris Cillizza of the Washington Post's The Fix rate the seat, held by former Anchorage Mayor Mark Begich, as the least likely Republican turnover of the seven; 538 rates Begich's chances at 55 percent. Stuart Rothenberg rates it as toss-up/tilt Democrat, while Charlie Cook, slightly more bearish on Begich's chances, rates it as one of five pure toss-ups.

Others may move in that direction given the latest polling from Rasmussen Reports. It shows an even race, 44 percent to 44 percent, between Begich and Republican challenger Dan S. Sullivan, and perhaps a bit surprisingly, Republican Lt. Gov. Mead Treadwell leading Begich 47 percent to 44 percent.

Public polls have been sparse in Alaska, but earlier polling from February 2013 to January 2014 showed Treadwell and Sullivan trailing Begich. Of perhaps more significance, however, is that only one poll, conducted in August against Treadwell, showed Begich reaching 50 percent. If the old rule is still in force -- the rule that says that an incumbent polling under 50 percent is in trouble -- then Begich has been threatened all along, and of course in 2008 he won by only a 48-percent to 47-percent margin over incumbent Ted Stevens after Stevens was convicted on criminal charges that were later overturned as tainted by prosecutorial misconduct.

Both these Republicans have significant credentials. Treadwell has long been involved in Alaska state government and its relations with the federal government; he worked for former Gov. Walter Hickel's Yukon Pacific firm and in his administration in the 1990s and was in charge of the Exxon Valdez cleanup in 1989. Sullivan was appointed state attorney general and head of the state's department of natural resources; Democrats have attacked him for working out of it, but since he did so as a Marine Corps Reserve officer and on the post-9/11 National Security Council staff, that doesn't seem like a strong attack line. Begich also has good credentials as a former Anchorage mayor himself and as the son of Nick Begich, the Alaska congressman who was lost in a plane crash along with House Majority Leader Hale Boggs in 1972.

We’ll see if the Rasmussen findings are reflected in other polls.