Tunisia's Ennahda party, the first Islamist movement to secure power after the 2011 "Arab Spring" revolts, conceded defeat on Monday in elections that are set to make its main secular rival the strongest force in parliament.
Official results from Sunday's elections – the second parliamentary vote since Tunisians set off uprisings across much of the Arab World by overthrowing autocrat Zine El-Abidine Ben Ali – were still to be announced.
But a senior official at Ennahda, which ruled in a coalition until it was forced to make way for a caretaker government during a political crisis at the start of this year, acknowledged defeat by the secular Nidaa Tounes party.
"We have accepted this result, and congratulate the winner Nidaa Tounes," the official, Lotfi Zitoun, told Reuters. However, he repeated the party's call for a new coalition including Ennahda. "We are calling once again for the formation of a unity government in the interest of the country."
Earlier, a party source said preliminary tallies showed the secular party had won 80 seats in the 217-member assembly, ahead of 67 secured by Ennahda.
"According to the preliminary results, we are in the lead and in a comfortable position," one Nidaa Tounes official said, without confirming figures given by the first source.
One of the most secular Arab countries, Tunisia has been hailed as an example of political compromise after overcoming a crisis between the secular and Islamist movements and approving a new constitution this year that allowed the elections.
Electoral authorities were due to give preliminary results later on Monday, but larger parties had observers at polling stations to oversee the initial counts, allowing them to tally results unofficially.
Ennahda, which espouses a pragmatic form of political Islam, won Tunisia's first free election in 2011 after Ben Ali fled protests against corruption and repression, and went into exile in Saudi Arabia.
The party formed a coalition government with two secular partners but had to stand aside in the crisis that erupted over the murder of two opposition leaders by Islamist militants.
During campaigning Ennahda cast itself as a party that learned from its mistakes, but Nidaa Tounes appeared to have capitalized on criticism that it had mismanaged the economy and had been lax in tackling hardline Islamists.
Ben Ali Remnants
A Nidaa Tounes victory will open the way for the return of some Ben Ali-era figures who have recast themselves as technocrats untainted by the corruption of his regime, but possessing the administrative skills to run the country.
Since its revolt, the small North African state has fared better than its neighbors which also ousted long-ruling leaders during 2011, avoiding the turmoil suffered by Egypt and the outright civil war of Syria and chaos of Libya.
Many Tunisians are proud of their history of liberal education and women's rights dating back to Habib Bourguiba, the first president after independence from France, and Essebsi portrayed his party as the force of modernity.
But the country also has an undercurrent of hardline, ultra-conservative Islam, and security forces are engaged in a low intensity conflict with militants.
Tunisian militant fighters have long been prominent among jihadis in foreign wars dating back to the 1980s Soviet occupation of Afghanistan, and more than 3,000 are estimated to be fighting for Islamic State now in Syria and Iraq.
Even with an advantage over Ennahda, Nidaa Tounes will need to form a coalition with other parties to reach a majority in the parliament and form a new government.
Ennahda may still be part of any cabinet. Before the elections, the party had called for a unity government to help Tunisia though the last stages of its transition and deal with tough austerity measures to revive economic growth.
Led by Beji Caid Essebsi, a former parliament speaker under Ben Ali, Nidaa Tounes emerged in 2012 as a political force by rallying opposition to the first Ennahda-led government when Islamists won around 40 percent of seats in the first assembly.
Nidaa Tounes drew from Ben Ali officials, smaller parties, and even union leaders to form an anti-Islamist front.
But Essebsi, a veteran politician since after independence, and Ennahda leader Rached Ghannouchi, an Islamist scholar who spent decades in exile in Britain, were also instrumental in the political compromise that pulled Tunisia back from the brink.
While the role of Islam in politics overshadowed the first election in 2011, jobs, economic opportunities and Tunisia's low-intensity conflict with Islamist militants were the main concerns of a country heavily reliant on foreign tourism.