Voting is underway in mainland France on Sunday in pivotal run-off elections that could hand a historic victory to Marine Le Pen’s far-right National Rally and its inward-looking, anti-immigrant vision — or produce a hung parliament and political deadlock. French President Emmanuel Macron took a huge gamble in dissolving parliament and calling for the elections after his centrists were trounced in European elections on June 9. The snap elections in this nuclear-armed nation will influence the war in Ukraine, global diplomacy and Europe’s economic stability, and they’re almost certain to underc…