Major rifts within the opposition have been cited as the biggest factor likely to thwart efforts by their leader Anwar Ibrahim to win control of government at the next election, due by 2013, although some analysts say a poll could be held as early as next year.
More than 1,500 opposition officials endorsed a document that spelled out their common goals after a daylong convention aimed at patching-up their differences.
The three-party alliance made unprecedented inroads in the 2008 general elections but those gains were also attributed to widespread anger over the government's handling of problems such as graft and racial inequality.
Speaking to the party faithful in the eastern state of Sabah on Sunday, Anwar says Malaysia is witnessing a battle between the common interests of the people against the ruling elites.
"At times the contentious battle is between the interests of the masses, the public, of the nation, of the people, and the interests of a special elite group, either family, cronies or political elements. And in this battle – [a] contentious battle -- invariably the public will lose," he said.
Spats within the opposition stem largely from ideological differences among the three opposition parties which consist of a conservative Islamic group that caters to the Malay Muslim majority; a secular, left-leaning party whose members are mostly from the ethnic Chinese and Indian minorities; and Anwar's multiracial party, considered the bridge between the other two partners.
However, these parties will still require a substantial swing if they are to win power at the next election. The National Front, spearheaded by the all powerful United Malays National Organization (UMNO) has dominated Malaysia politics since independence in 1957.