CHARLOTTE, N.C. – President Barack Obama consoled victims of Hurricane Isaac along the Gulf Coast on Monday and stoked the enthusiasm of union voters in the industrial heartland, blending a hard political sell with a softer show of sympathy on the eve of the Democratic National Convention.

At times like these, “nobody’s a Democrat or a Republican, we’re all just Americans looking out for one another,” the president said after inspecting damage inflicted by the storm and hugging some of its victims. He was flanked by local and state officials of both parties as he spoke in LaPlace, La.

There was nothing nonpartisan about his earlier appearance in Toledo, Ohio. There, the president said Republican challenger Mitt Romney should be penalized for “unnecessary roughness” on the middle class and accused him in a ringing labor Day speech of backing higher taxes for millions after opposing the 2009 auto industry bailout.