So just how crafty was Bernie Sanders in traveling to the Vatican rather than campaigning in New York for the April 19 presidential primary? Very, I would say.

New York is one of the country's most Catholic states; roughly 38 percent of the population is Catholic. The suburban swing counties are even more Catholic—verging toward fifty percent on Long Island, according to a survey by the Public Religion Research Institute. After speaking at a Vatican conference on social justice issues, Sanders even managed to cross paths with Pope Francis. New Yorkers have always turned out big for popes, including Francis.

Such quick overseas political campaign trips are very much a part of New York politics, although to Israel more so than to the Vatican. Polls in the New York Democratic primary vary a lot, but one considered reliable—conducted by Marist College—shows Hillary Clinton leading Sanders by 17 percentage points. Others show a tightening race.

Sanders has faced a very much uphill battle in the Empire State, given that New Yorkers twice elected Clinton to the U.S. Senate while well aware that she'd probably use the position as a springboard to run for president. But as Todd Purdum noted in a piece for Politico, anything can happen in a New York primary, with its contentious media atmosphere.

It will be interesting to see how Sanders' views on the Israeli-Palestinian dispute play with New York voters. His call for respect for Palestinians very much echoes the positions of a series of popes, but it's not something normally heard from politicans campaigning for New York votes.

Sanders' trip to Rome was the political equivalent of a Hail Mary pass. Once in a while, those passes connect.