Istanbul, Turkey CNN  — 

Turkey will have a runoff election on May 28 after longtime leader President Recep Tayyip Erdogan was forced into a second round with only a narrow lead over his rival, Kemal Kilicdaroglu.

Neither candidate achieved the required 50% to take the presidency outright, after 100% of ballot boxes were opened, according to Turkey’s Supreme Election Council. All ballot boxes in the country were opened and the voter turnout rate is 88.92%, council chairman Ahmet Yener said.

But Kilicdaroglu now faces a tough battle to win the second round after Erdogan performed better than some opinion polls had suggested.

Official final results for Turkey’s election will be announced on Friday, the chairman of Turkey’s supreme election council Ahmet Yener said.

With the final count, the electorate will turn to a second round of voting that could extend Erdogan’s 20-year grip on power, or set the stage for a change in political direction.

Erdogan supporters wave flags outside the Justice and Development (AK) Party headquarters in Ankara, Turkey, after the president performed better in the first round than pre-election polls suggested.

Each candidate looked to re-energize voters once results began to surface in the early hours of Monday, in remarks that framed their contrastingly conservative and secular approaches to power.

Erdogan said he was “already ahead” of his “closest rival.”

“We are already ahead of our closest rival by 2.6 million votes. We expect this figure to increase with official results,” he commented.

He added that his camp does not know yet “if the presidential election is over in the first round,” but said, “We believe we will finish this round with over 50% of the votes.”

The leader of the ruling Justice and Development (AK) Party received a litany of criticism in the months preceding the election, fielding accusations of negligence following the deadly February 6 earthquake, and overseeing an unorthodox fiscal policy that has plunged the nation into a cost of living crisis.

His decision to maintain close relations with Russia amid the Kremlin’s war in Ukraine has also caused friction with NATO allies, after he blocked requests for Finland and Sweden’s accession to the transatlantic military alliance. He campaigned on a manifesto championing the stability of his long rule, independent foreign policy and lowering the retirement age.

Kilicdaroglu, who represents an election coalition of six opposition parties, has promised an overhaul of Erdogan’s Islamist-leaning policies in favor of a