By Zeeshan Haider

ISLAMABAD (Reuters) - Pakistan's beleaguered President Pervez Musharraf canvassed ruling party parliamentarians on Thursday to support his bid for five more years in power.

U.S. ally General Musharraf wants to be re-elected by sitting national and provincial assemblies between mid-September and mid-October, before their dissolution for a general election due by the turn of the year.

His plans could come unstuck if the Supreme Court were to uphold constitutional challenges. The opposition is likely to mount those against both his being re-elected by the outgoing assemblies, and while still army chief.

Musharraf flew to the central city of Faisalabad to rally support from legislators belonging to the ruling Pakistan Muslim League Quaid-e-Azam (PML-Q), a party he cobbled together after coming to power in a 1999 coup.

"The President told the parliamentarians that he is going to contest the election in uniform and it is fully according to the law and constitution," Minister for Textile Industries Mushtaq Ali Cheema told Reuters, after Musharraf met with more than 100 legislators from the national and provincial Punjab assemblies.

"We assured full cooperation and support to him and told him we stand by him."

A senior government official said Musharraf, who is going through his weakest period, planned several more meetings to rally support in the PML-Q.

The party is in disarray, and fears a voter backlash due to its support for a president whose popularity has plummeted.

Many parliamentarians are disgruntled the leadership had not taken them into confidence ahead of politically damaging actions, like a vain attempt to replace Supreme Court Chief Justice Iftikhar Chaudhry.

They have also been upset by Musharraf's attempt to forge an alliance with their main rival the Pakistan People's Party, led by self-exiled former premier Benazir Bhutto.

Legal moves by ex-prime minister Nawaz Sharif to return to Pakistan from exile have added to uneasiness in the ruling party's ranks. Sharif had led the PML, but it split after he was ousted eight years ago.

Musharraf almost invoked emergency powers last week, as Pakistan has reeled from a series of bomb attacks by Islamist militants allied to al Qaeda.

If he had gone ahead, analysts suspect his real motive would have been to circumvent constitutional obstacles that lie ahead.

Opposition figures, including Bhutto, demand Musharraf resign from the army and seek re-election from the assemblies formed after the general election.

The New York Times reported on Thursday that the United States is quietly pushing Musharraf to share power with Bhutto.