* Nasheed wins, but fails to secure majority in first round
* Nasheed's rivals demand Sunday's planned run-off be delayed
* Political turmoil hits vital tourism industry
* Court annulled September poll results; police halted October poll
Former leader Mohamed Nasheed edged ahead in the first round of the Maldives presidential race on Saturday, but his lack of a clear majority will mean a run-off with his nearest rival as early as Sunday.
Nasheed, the Indian Ocean state's first democratically elected leader, who was ousted from power last year, won 46.66 percent of the vote, according to provisional results.
The poll was the Maldives' third attempt to elect a new president in as many months and the two main political factions again accused each other of blocking a free and fair election.
Nasheed's rivals could turn to the Supreme Court to delay the second voting round, which they have demanded be postponed.
The repeated delays have drawn criticism from international observers, including the United States, and further tarnished the image of a country better known for its luxury resorts and pristine beaches than its recent bouts of political turmoil.
Whoever wins will face a rise in Islamist ideology, human rights abuses and a lack of investor confidence. The political crisis has hit tourism, a vital source of earnings, and the Maldives has faced fuel shortages because it is unable to pay suppliers on time as foreign exchange reserves dwindle.
"It is important now that the electoral process move forward swiftly to its conclusion, with the holding of the second round," said Donald McKinnon, the Commonwealth Secretary-General's Special Envoy, after the vote.
"It is unreasonable and unacceptable for parties to continue to demand changes to an agreed election date."
Nasheed's main opponent is Abdulla Yameen, a half-brother of Maumoon Abdul Gayoom, who ruled the islands for 30 years and was considered a dictator by opponents and rights groups. Yameen won 29.88 percent of the vote, while resort tycoon Gasim Ibrahim, a finance minister under Gayoom, secured 23.46 percent, according to provisional results with 472 out of 475 ballot boxes counted.
It is unclear who will run the Maldives in the absence of a new president. The incumbent Mohamed Waheed says he will not stay on after his term expires on Nov. 11, despite a Supreme Court ruling asking him to do so until a replacement is elected.
"My view is that if we don't have elections tomorrow there is a serious risk of indefinite delay as now Waheed is asked to stay on by the Supreme Court," said Nasheed. "Our opponents know that they will lose in a fair fight."
The presidential candidates were meant to sign a register to verify the details of an electorate of nearly 240,000, after allegations that voter lists contained dead people and children.
Ali Shiyam, deputy chairman of Nasheed's Maldivian Democratic Party, said Nasheed's rivals had refused to do this for the lists prepared in the event of a run-off. "Our opponents are, once again, trying to subvert democracy by refusing to sign the voter lists for tomorrow's election," he said.
A Sept. 7 vote was annulled based on a secret police report which found vote rigging while an October poll was halted by police after a Supreme Court ruling.
Many voters feared Saturday's result could be annulled again through meddling either from politicians or the police.
"I just hope the Supreme Court doesn't interfere again tonight," said Ameena Ali, 63, who voted in Male, the capital of the 1,200-island archipelago of 330,000 Sunni Muslims.
A former street activist, Nasheed came to power in 2008 but was ousted in 2012 in what his partisans say amounted to a coup. He once held a cabinet meeting underwater to highlight the threat of global warming to the low-lying archipelago.
His removal led to protests by his supporters and a police crackdown. A Commonwealth-backed commission of inquiry later concluded that his ouster did not constitute a coup.
The Election Commission had planned for a possible run-off on Sunday, but Gasim's party wants the Supreme Court to postpone this, demanding time for the candidates to campaign. Yameen said more time was needed to verify the electoral roll, asking for the run-off to be held after Nov. 13. Citing alleged voting irregularities, he also questioned the credibility of the poll.