Turkish President Recep Tayyip Erdogan took an early lead on Sunday in a landmark election that could extend his two-decade grip on power.
The Anadolu state news agency showed the 69-year-old picking up more than 51 percent of the vote and his secular rival Kemal Kilicdaroglu trailing with nearly 43 percent.
But Anadolu's figures were based on around 60 percent of the ballots and Kilicdaroglu claimed that his party's own vote count showed him winning.
"We are leading," Kilicdaroglu tweeted after Anadolu's results started coming out.
Most of Anadolu's early votes appeared to be coming from heavily pro-government districts and Erdogan's lead was shrinking as the number of counted ballots grew.
"We are seeing a positive picture, according to our data," opposition Republican People's Party (CHP) spokesman Faik Oztrak told reporters.
"We will start to give the numbers when the number of opened ballot boxes reaches a meaningful level."
A separate count reported by the pro-opposition Anka news site showed the two leaders locked in a dead heat and falling just short of the 50-percent threshold needed to avoid a May 28 runoff.
Anka and Anadolu showed third-party candidate Sinan Ogan picking up five percent of the vote.
Most pre-election polls showed 74-year-old opposition leader Kilicdaroglu enjoying a slight advantage over Erdogan.
Huge turnout
Turnout was expected to be huge in what has effectively become a referendum on Türkiye's longest-serving leader and his Islamic-rooted party.
Erdogan has steered the nation of 85 million through one of its most transformative and divisive eras in the post-Ottoman state's 100-year history.
Türkiye has grown into a military and geopolitical heavyweight that plays roles in conflicts from Syria to Ukraine.
The NATO member's footprint in both Europe and the Middle East makes the election's outcome as critical for Washington and Brussels as it is for Damascus and Moscow.
Erdogan is lionized across swathes of conservative Türkiye that witnessed a development boom during his rule.
More religious voters are also grateful for his decision to lift secular-era restrictions on headscarves and introduce more Islamic schools.
"My hope to God is that after the counting concludes this evening, the outcome is good for the future of our country, for Turkish democracy," Erdogan said after casting his ballot in Istanbul.
'We all miss democracy'
Erdogan's first decade of economic revival and warming relations with Europe was followed by a second one filled with social and political turmoil.
He responded to a failed 2016 coup attempt with sweeping purges that sent chills through Turkish society and made him an increasingly uncomfortable partner for the West.
The emergence of Kilicdaroglu and his six-party opposition alliance -- the type of broad-based coalition Erdogan excelled at forging throughout his career -- gives foreign allies and Turkish voters a clear alternative.
A runoff on May 28 could give Erdogan time to regroup and reframe the debate.
But he would still be hounded by Türkiye’s most dire economic crisis of his time in power, and disquiet over his government's stuttering response to the February earthquake that claimed more than 50,000 lives.
"We all missed democracy," Kilicdaroglu said after voting in the capital Ankara. "You will see, God willing, spring will come to this country."
'Can't see my future'
Pre-election polls indicated Kilicdaroglu would win the youth vote -- nearly 10 percent of the electorate -- by a two-to-one margin.
"I can't see my future," university student Kivanc Dal, 18, told AFP in Istanbul on the eve of the vote.
Erdogan "can build as many tanks and weapons as he wants, but I have no respect for that as long as there is no penny in my pocket".
But nursery schoolteacher Deniz Aydemir said Erdogan would get her vote because of the economic and social progress Türkiye made after half a century of corruption-riddled secular rule.
The 46-year-old also questioned how a country could be ruled by a coalition of six parties -- a favorite attack line of Erdogan during the campaign.
"Yes, there are high prices... but at least there is prosperity," she said.
Erdogan's campaign became increasingly tailored to his core supporters as election day neared.
He branded the opposition a lobby that took orders from outlawed Kurdish militants and was bankrolled by the West.
Erdogan's ministers and pro-government media referred darkly to a Western "political coup" plot.
The opposition began to worry that Erdogan was plotting how to hold on to power at any cost.
Erdogan bristled when asked on Friday night television if he would agree to leave if he lost.
"This is a very silly question," he fumed. "We would do what democracy requires."
