evidence: When Gretchen Whitmer was the opposition leader in the Michigan Senate she would spend her days in pitched battle with her political foes. But when they were done, the Democrat and her Republican counterpart would shut up shop, head to the bar and thrash it all out over a beer. American politics has become incomparably more polarised in the decade since then, yet Whitmer, now the state governor, still paints herself as a champion of bipartisan understanding and no-nonsense, pragmatic politics. "The governor is tough," said Curtis Hertel Jr, her former legislative director and friend for nearly three decades. "I think she is someone who is willing to work across the aisle and get things done."