BUCHAREST (Reuters) -- Romania's president Traian Basescu is likely to escape impeachment in a referendum on Saturday but faces a daunting task reviving stalled reforms and anti-corruption efforts.

Huge crowds have demonstrated support for Basescu at rallies across Romania and abroad since he was suspended by parliament in April on charges of abusing power.

Opinion polls show Basescu, the country's most popular politician, is set to survive the vote. Many regard his return as Romania's only chance to rub out widespread graft that plagues all areas of society.

But Basescu, 55, is still likely to struggle to overcome feuding among the ruling centrists and the opposition, and a growing opposition towards fighting graft among some politicians, which have damaged Romania's reforms.

The political wrangling led to the suspension of Basescu and forced the May 19 referendum which was required under Romanian law as a followup to the parliamentary vote.

"Basescu has been instrumental in speeding up reforms in a transparent and modern way. He is seen in the EU as a man who delivered reforms and was one of the big engines behind EU membership," said one diplomat in Bucharest. "But he has alienated himself from the political consensus and you wonder now whether he is now part of the solution or part of the problem."

Romania still has to prove to the European Union, which it joined in January, that it is serious about fighting graft and reforming its outdated agricultural sector to avoid sanctions, possibly as soon as in June.

EU diplomats say member states are increasingly concerned about Romania's progress in fighting crime, with some going as far as to say the Black Sea state, and its smaller southern neighbor Bulgaria, were admitted too early.

A centrist coalition backed by Basescu after 2004 elections has made vast progress in overhauling a communist-era justice system and state institutions.

But the country is still ranked as the most corrupt in the EU on Transparency International's corruption perception index.

Observers say there appears to be little chance that bickering in Bucharest will subside after the referendum as political groups jostle for influence. Instability may last as long as until the next parliamentary election in late 2008. "We will be having the same political system reproduced," said commentator Emil Hurezeanu. "If Basescu uses his victory to create consensus, it would be good."

Basescu's combative style has helped fuel disagreements that led to a split in Bucharest's centrist coalition and caused further delays in justice reforms, some observers say.

A former sea captain, Basescu swept into power in 2004. During his term, he led the opening of the archives of the feared communist-era secret police and issued Romania's first official condemnation of communism.

The constitutional court has rejected charges he overstepped his powers. In April, parliament removed him from office for 30 days pending the impeachment referendum.

"It's out of the question that I would abandon my commitments. I will make sure that the judiciary will become more independent," Basescu told an evening talk show on Tuesday.