The message of John Edwards’ presidential campaign is, in a word, urgency. Elizabeth Edwards underlined it recently in a somber video appeal for contributions. “Sometimes we put things off, don’t we?” she said. “We think we have all the time in the world. Well, we don’t.” Poverty, the war, global warming, health care for the uninsuredthey can’t wait, she said, because people are suffering. Her own urgency is palpable; she was diagnosed with incurable cancer in March.

Elizabeth Edwards will be in Durham and Raleigh the next two weeks to read from her book, Saving Graces: Finding Solace and Strength from Friends and Strangers, out in paperback with a new chapter about the diagnosis. She may be asked about polls showing the campaign is in trouble and that slack fundraising forced John Edwards’ decision to sign up for public financing.

Meanwhile, Barack Obama drew a youthful crowd of 20,000-plus in New York City Thursday with his message not of urgency but optimism. The difference is fundamental. John Edwards says we know what to do on the issues, and he’ll fight for what’s right before it’s too late. Obama’s response: Such fights are futile without first taking the time to forge a new politics of inclusion, not confrontation, and reach across lines of party, ideology, race and age. “When I see a crowd like this,” Obama declared, “I see that the American people are not the problem, the American people are the answer. Let’s go change the world.” Whoever’s right, Obama’s lead on Edwards is greatest among young voters (18-29), for whom time hopefully isn’t short. They’re a key reason henot Edwardsremains Hillary Clinton’s primary challenger.