WASHINGTON (CNN) -- Former North Carolina Sen. John Edwards, a candidate for the Democratic Presidential nomination, said Monday he remains "committed to this crusade," five days after he announced his wife Elizabeth's cancer had returned.

"People want to know why I continue this campaign for president --why both Elizabeth and myself are so committed to this cause, to this crusade, and I will tell you why," Edwards said during a Communication Workers of America conference. "Because I want everybody in this country to have the same chances that I have had. I came from a place of having nothing to having everything and in today's America it is so hard for people to work themselves up."(Watch video: Democratic candidates address CWA)

At the conference, attended by more than 600 members of Communication Workers of America, Edwards described himself as a candidate with big ideas.

"You will figure out pretty quickly, I am not the candidate of little ideas," he said. "I think we need big bold change in America. It is not enough for us to have small baby steps anymore."