* Congolese clamour to vote, fear further election delays
* President Kabila coopts opposition to ease pressure for vote
* Economy worsens, corruption spreads
* Officials reject comparisons with slide to war in 1990s
KINSHASA, June 7 (Reuters) - Arnaud Kalala had queued for hours in Kinshasa's rainy season heat to register to vote in an overdue election to replace Congolese President Joseph Kabila, but the 44-year-old civil servant had little faith in the new deadline.
"With what's going on here, it'll be a miracle if it happens by Dec. 31," said Kalala, surveying an impatient crowd of 100 residents outside a secondary school.
Congolese have flocked to register in Kinshasa since voter enrolment began in the capital last week. Many said they hoped for an eventual end to two decades of Kabila family rule while holding out little hope for a vote this year.
The election should have taken place by the end of last year and voter registration began in some parts of the country almost a year ago, but the election commission has said technical delays may mean the new deadline has to be pushed back.
In the meantime, corruption and violence are again spreading across Democratic Republic of Congo, long consigned to the ranks of the world's poorest countries by poor governance and a myriad of militia groups, despite copious mineral resources.
The currency has lost more than half of its value in the past year and inflation is nearing 30 percent, prompting comparisons with the later rule of Mobutu Sese Seko, who was eventually ousted by Kabila's father in a civil war that went on to kill millions.
"Today, we have to ask the question: do we let Congo collapse again?" said Daniel Mukoko Samba, a former budget minister under Kabila, referring to the 1990s, when massive corruption and rifts with Western donors under Mobutu sparked hyperinflation and economic disintegration.
When Kabila, in power since his father's assassination in 2001, refused to step down at the end of his mandate in December, many Congolese hoped protests could unseat him.
Instead, he has weathered all challenges, maintaining a firm grip over the security forces that suppressed anti-government protests last year, killing dozens.
He has also co-opted opponents with government posts -- despite fears he aims to change the constitution so he can run again, a charge he has neither confirmed nor denied. Those opponents have duly stopped agitating for elections.
The planned funeral of leading opposition light Etienne Tshisekedi was expected to bring hundreds of thousands onto the streets in a rare moment of unity against Kabila.
But Tshisekedi's party is feuding with officials over the burial place while the longstanding icon of Congo's democratic struggle has languished since February in a morgue in Brussels, where he went for medical treatment shortly before he died.
The effects of all this 'glissement' -- slippage, as the Congolese call it -- has been to aggravate crises in the vast, central African nation once under Belgian colonial rule.
More Congolese fled their homes due to violence last year than Syrians or Iraqis. An insurrection in Congo's normally peaceful centre has killed hundreds since last August. Thousands escaped from Kinshasa's maximum security prison last month after an attack linked to a separatist group. Several expatriates have been kidnapped.
"The administration is falling apart in the territories (areas outside Kinshasa), which have become practically uncontrollable," said Jean Omasombo, a Congo expert at the Royal Central Africa Museum in Belgium.
"HEADING FOR DISASTER"
Large companies, even ones used to Congo's risk, are shying away. They are reluctant to speak on the record to avoid angering the government, but some of their actions suggest a move towards the exit.
Last year Freeport McMoRan sold off its stake in the Tenke copper mine, one of the world's largest. It cited a desire to reduce its debts, though analysts say the operating environment played an important role in the decision.
The Chamber of Commerce last week decried a deteriorating business climate in Congo's copper-mining southeast, including harassment by tax authorities to the tune of over $300 million in what it said were bogus customs duties.
"We've clearly seen diminishing interest in Congo among large companies, especially Western ones," said Vincent Rouget, Congo analyst at Control Risks.
Kabila's former Western allies are deserting him, just as they did Mobutu before him. The European Union and United States both slapped sanctions last week on Congolese officials who they say have committed human rights abuses and impeded progress toward elections. Western donors rejected Congolese requests for financial support last year.
Former Kabila minister Mukoko, now an economics professor at Kinshasa University, said a decade after donors withdrew support for Mobutu's Zaire, the country fell apart as war engulfed the east. "If the government says to itself 'we don't need a dialogue, we are going to do what we want,' we are heading for disaster," he said.
Congolese officials reject comparisons with the dying days of Mobutu, whose reign ended with regional wars that sucked in more than a half-dozen countries between 1996 and 2003.
"Mobutu left due to a rebellion supported by the neighbouring countries," said Tryphon Kin Kiey Mulumba, a leader in Kabila's ruling coalition. "President Kabila ... has the support of the sub-region."
That support is being tested. Traditional ally Angola continues to publicly back him but has expressed growing alarm over insecurity as fighting in Kasai has driven 20,000 refugees across its border.
(Editing by Tim Cocks and Philippa Fletcher)