NEW YORK -- Former presidential candidate John Edwards still hasn't made a Democratic presidential endorsement.

But the former North Carolina senator seemed to stop just short of it Friday.

The superdelegate tells NBC's "Today" show that Barack Obama can unite the Democratic party, bring in new voters and get people excited about change.

Edwards said Hillary Rodham Clinton has made a very strong case for her candidacy, but adds "it's very difficult to make the math work" for her nomination.

Edwards dropped his bid for the White House in January. He also was the Democratic vice presidential nominee during Democrat John Kerry's unsuccessful presidential run in 2004.

Edwards lives with his family in Chapel Hill.