Washington ? Hours after telling the world that his wife’s cancer had returned for good, John Edwards was in New York raising money.

Cancer or no, the campaign goes on. And that means Edwards must continue to court big-time donors despite questions that might arise over the viability of his second run for president.

Already, he trails far behind front-runners Barack Obama and Hillary Rodham Clinton in fundraising for the Democratic nomination. Political observers have said top-tier candidates must prove by the next finance-reporting deadline, March 31, that they have what it takes to stay in the race.

Still, Edwards has led in crucial polls in Iowa, the home of the first caucus. And he’s been working hard in Nevada, another early-round primary. He’ll be there again this morning at a health-care forum sponsored by the Service Em-ployees International Union, which he’s been courting.

In the short term, major donors will pay close attention to how Elizabeth Edwards acts, Duke University political scientist David Rohde said.

“If she’s functioning OK, then there’s not much impact,” Rohde said. “The public will see them going on, and they won’t think he’s selfish because he’s out there. I think if donors believe he can in fact go on with his campaign, they will in fact make the investment if he looks attractive on other grounds.”