Tens of thousands of French people on Sunday marched in the streets in Paris to voice their supports for the bill in favor of gay marriage before the debate opens next Tuesday.
Chanting the slogan of "equal rights" with rainbow flags in hands, the demonstrators converged to the Place de la Bastille.
Heavy weights from the Left-wing, including First Secretary of the Socialist Party Harlem Desir, Paris Mayor Bertrand Delanoe, Housing Minister Cecile Duflot, Co-Chairman of the Left Party Jean-Luc Melancho, National Secretary of the French Communist Party Pierre Laurent, were all presented in the procession.
Police estimated that the number of the participants was at 125,000, but organizers put the number at 400,000.
"Some have tried to believe that there was a majority of French people opposed to this law," said Laurent, thus "it's important by demonstration in the street to show that most of the French society is ready for this progress," he added, referring to the anti-gay marriage protest on Jan. 13 which brought together 340,000 people according to the police, but 1 million by organizers.
Former health minister Roselyne Bachelot, one of a few militants from the major opposition party UMP, also appeared among the protesters who "personally" participated in the event, and said "it is important to have a majority in Parliament to vote for it."
The demonstration came just two days ahead of the parliament debate scheduled to open on Tuesday over the bill of "marriage for all", a campaign promise of French President Francois Hollande, to legalize same-sex marriage and to allow adoption for same-sex couples.
Last Friday, in his meeting at the Elysee Palcace with Frigid Barjo, president of the Manif for All which is a main association against the same-sex marriage, Hollande reiterated his determination to see parliament to adopt this project.
Moreover, Prime Minister Jean-Marc Ayrault on Saturday called for a "strong commitment" of those pro-gay marriage, expressing his optimistic outlook to the result of the parliament debate as he believed that "the law will be passed, and even with a large majority."
The latest Ifop poll found that up to 63 percent of French voters back gay marriage, against 60 percent in earlier January, while pro-adoption rate arrived at 49 percent.
After the Socialist government approved the bill to allow same-sex couples to marry and adopt children in November 2012, religious leaders and conservatives mobilized against the move with France's leading Roman Catholic Church warning that the bill would destabilize the French society's equilibrium.
Until Friday night, more than 5,000 amendments to the bill had been tabled.