You might know Graham Platner as the Maine Senate candidate whose past included a Nazi-associated tattoo. Yet despite serious questions about his background and judgment, he has effectively won the Democratic primary.

Many Democrats in Maine appear either unwilling to fully confront Platner’s controversial history or willing to overlook it to defeat Republican U.S. Sen. Susan Collins. Both responses reflect a dangerous erosion of political standards, one reminiscent of the partisan rationalizations that helped Republicans excuse President Donald Trump’s many flaws.

Democrats should demand better from their candidates. Rallying behind any nominee simply because of party affiliation, even against one of the Senate’s most moderate Republicans, risks degrading candidate quality and deepening America’s political polarization.

Platner's troubling record isn't a secret

Platner, 41, is a deeply flawed candidate whose campaign should have faced far greater scrutiny from the outset. Serious concerns began with the revelation that he had long displayed a skull-and-crossbones tattoo that resembles the Totenkopf, a symbol widely associated with Nazi imagery, on his chest. Platner claims he did not understand its meaning for........

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