Meanwhile, Biden’s circle has identified what they see as their potential voting blocs: Reagan Democrats, Jews, an LGBT base that largely credits him with pushing President Barack Obama into supporting gay marriage, and Rust Belt voters. They believe he’ll benefit from better stump skills than any of the other candidates running.

And there’s an emerging primary state calculus: while Clinton and Sanders duke it out in New Hampshire, where Biden barely played in either of his two previous presidential runs, his main focus would be on South Carolina — where he could draw on his connections to former Sen. Fritz Hollings, former state Democratic chair Dick Harpootlian and black voters, as well as the relationships of his 2012 political director Trip King, who lives in Columbia and was his state director for the 2008 run.

South Carolina, goes the thinking, would be the first real open primary and the first with a diverse electorate, and that would power the argument they’re making about Biden’s appeal to broader constituencies.