A decade’s worth of grudges and feuds between the Democratic establishment and the insurgent left is coming to a head in one election this year: Michigan’s Senate primary.Key takeawaysMany long-simmering grudges between the establishment Democratic Party faction and a faction supporting Sen. Bernie Sanders have come to the fore in Michigan’s Senate primary.Dynamics involving gender and race, concerns over electability, and claims of establishment malfeasance closely mirror dynamics in Sanders’s two presidential runs.Every intra-Democratic controversy over Israel — from the influence of AIPAC to claims of antisemitism — has come up too, showcasing a party with some bitter divides.The contest...