But in an era when voters so often grow disenchanted with those they send to Washington, the easy familiarity of a political dynasty could tip a close race.

“It’s not trivial,” the Democratic pollster Mark Mellman said. “When you go to McDonald’s, you know what kind of hamburger you’re going to get. With a Landrieu or Pryor or Begich, you have some real idea of what you’re getting. And it’s something you like.”…

Democratic legacy candidates have not been shy about trying to offset their disadvantages by capitalizing on family reputations. In the Alaska ad, Mark Begich’s wife says: “We share him with every Alaskan, like his father before him. Mark is clearly his father’s son.”