Champagne, a Frenchman who is a former Blatter adviser, on Monday became the first person to declare his candidacy for football's top job, saying he will seek the five required nominations.
"We need a different FIFA, more democratic, more respected, which behaves better and which does more," said Champagne, a former diplomat who unexpectedly left FIFA in 2010 after 11 years of service.
Before being re-elected unopposed in 2011, Blatter said this would be his final four-year term. But the 77-year-old Swiss official has hinted he could go for a fifth term in 2015.
Asked if he could beat Blatter, Champagne said: "No, I don't think. He is someone of relevance."
Pressed repeatedly to say if he would stand against Blatter, Champagne responded vaguely.
"I don't know what he will do," Champagne said. "I am telling you that I am standing, but I don't know what will happen in the next four months."
UEFA President Michel Platini is also mulling over whether to seek the post.
Before entering football, Champagne's diplomatic postings included four years in Los Angeles as deputy consul-general. He worked as protocol chief when France hosted the 1998 World Cup, then joined FIFA soon after Blatter was elected.
Troubled relations with confederations were reportedly a factor in Champagne leaving FIFA in January 2010.
As international relations director, Champagne's work was acclaimed but reportedly angered some confederation presidents.
Pele has given Champagne his support.
"I know his vision of football and the future of the game and for this reason I trust him," Pele said on a video shown at the launch. "We have worked together for many years and he has the experience as he has been in FIFA for a long time.
"I am a friend of everyone who loves football and I want the best for football and he is a person everyone can trust."
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