Some Senate Democrats may be too goshdarned likable to vote out

Republicans face a similar obstacle in Virginia where Sen. Mark Warner, a former governor, awaits. Sen. Mark Udall, whose family name is legendary in Democratic circles, is up for reelection in Colorado. Both have the type of reputations that make them more than just a generic member of their party. Warner has long inculcated a reputation as a centrist, and polls have reported his approval rating north of 60 percent.

Udall isn’t as well-liked, but more voters than not have a favorable image of him as he begins his re-election campaign: A survey from the Democratic firm Hickman Associates International, conducted on behalf of the Consumer Energy Alliance (a group that supports building the Keystone XL Pipeline), found 47 percent of state residents saw him very or somewhat unfavorably – only 26 percent viewed him unfavorably.

Those are the kind of numbers Democratic operatives say they can use to make the contests a local matchup of personalities, not just in the troika of blue states but possibly with Mark Pryor in Arkansas and Mary Landrieu in Louisiana. Shaheen, for instance, can talk about funding she delivered for a local firehouse while Republicans talk breathlessly about the president and Reid.

It’s a strategy they argue worked well in 2012, when Republicans tried and failed to make an array Senate races a national referendum.