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Bernie is learning the hard way that Hillary’s support extends well beyond the Deep South.

Following his rout in New York last week, and in the face of a potential blowout today in five Northeastern states, Sanders may regret dismissing Clinton’s string of victories in the South by calling it “most conservative part of this great country.” Clinton enjoys imposing leads in delegate-rich states like Pennsylvania and Maryland, and is expected to lock up Connecticut and Delaware as well. All those states have sizable minority populations and closed primaries in which voting is restricted to registered Democrats. Sanders’s best chance is in Rhode Island, where a mere 33 delegates are in play.

Even if he can keep it close in Pennsylvania and elsewhere, the delegate math is such that the main question after tonight will be where the Sanders campaign goes from here. This is the last big primary day before June 7, when California and New Jersey vote, and it has all the makings of a turning point for a campaign that is out of ways to cut into Clinton’s lead.