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House debates drags on as PM nomination challenged

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Court accepts case seeking Pita disqualification

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Move Forward agenda at odds with military establishment

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Pita expected 'pre-planned' moves against him

(Recasts, adds detail, Pita comment, paragraphs 7, 14-15, parliament debate)

By Chayut Setboonsarng and Panarat Thepgumpanat

BANGKOK, July 19 (Reuters) - The leader of Thailand's election-winning Move Forward Party met fresh obstacles in his prime ministerial bid on Wednesday, as a court suspended him as a lawmaker and rivals mounted a parliamentary challenge to try to scuttle his nomination.

U.S.-educated liberal Pita Limjaroenrat has an extremely difficult path to the top job, needing the backing of more than half of the bicameral parliament and to overcome fierce resistance from a royalist military at odds with his party's anti-establishment ambitions.

The legislature convened for Pita's second shot at the top job on Wednesday but his rivals moved immediately to derail him by questioning the parliamentary rule under which he was nominated by his eight-party alliance.

As an hours-long debate ensued, the Constitutional Court separately announced Pita had been temporarily suspended as a lawmaker over an allegation that he violated election rules by holding shares in a media firm, taking on its second complaint against him in six days.

The suspension does not bar Pita from running for premier, and the 42-year-old had told Reuters in an interview on Tuesday that he was expecting "pre-planned" obstacles, describing efforts by the military to stop him as like a "broken record".

Thailand has been run by a caretaker administration since March and 65 days have passed since Move Forward's stunning May 14 election triumph over military-backed parties, in what was widely considered a clear public rejection of nine years of government controlled by generals.

"Thailand is not the same since May 14. We have come halfway from the people's victory and there is another half to go," a smiling Pita told the house as he acknowledged the court's suspension order, receiving fist-bumps and applause.

Wednesday's drama was the latest twist in a two-decade battle for power in Thailand between elected parties and conservatives, including the military, that has included political bans, court interventions, two coups and at times violent street protests.

Hundreds of Pita's supporters gathered peacefully in Bangkok to protest against the efforts to stop him, some carrying signs denouncing senators for refusing to support him.