Turkish voters delivered a rebuke on Sunday to President Recep Tayyip Erdogan as his party lost its majority in Parliament in a historic election that thwarted his ambition to rewrite Turkey’s Constitution and further bolster his clout.
The results represented a significant setback for Erdogan, who has steadily increased his power since being elected last year as president, a partly but not solely ceremonial post.
The prime minister for more than a decade before that, Erdogan has pushed for more control of the judiciary and cracked down on any form of criticism, including prosecuting those who insult him on social media, but his efforts appeared to have run aground on Sunday.
The vote was also a significant victory to the cadre of Kurds, liberals and secular Turks who found their voice of opposition to Erdogan during sweeping antigovernment protests two years ago. For the first time, the Kurdish slate crossed a 10 percent threshold required to enter Parliament.
Erdogan’s Justice and Development Party, or A.K.P., still won the most seats by far, but not a majority, according to preliminary results released Sunday night. The outcome suggests contentious days of jockeying ahead as the party moves to form a coalition government. Already, analysts were raising the possibility Sunday of new elections if a government cannot be formed swiftly.
With 99 percent of the votes counted, the A.K.P. had won 41 percent of the vote, according to TRT, a state-run broadcaster, down from nearly 50 percent during the last national election in 2011. The percentage gave it an estimated 258 seats in Turkey’s Parliament, compared with the 327 seats it has now.
“The outcome is an end to Erdogan’s presidential ambitions,” said Soner Cagaptay, an expert on Turkey and a fellow at the Washington Institute for Near East Policy.
Almost immediately, the results raised questions about the political future of Prime Minister Ahmet Davutoglu, who moved to that position from that of foreign minister last year and was seen as a loyal subordinate of Erdogan.
Speaking Sunday night from a balcony at the party headquarters in Ankara, Davutoglu struck notes of triumph and optimism, touting his party as the winner because it won the most seats, without mentioning the loss of its majority.
“The elections once again showed that the A.K. Party is the backbone of Turkey,” he said.
By law, Erdogan can call for new elections after 45 days if a coalition is not formed, and the political uncertainty sent Turkey’s currency, the lira, to a record low against the dollar in after-hours trading.
The vote turned on the historic performance at the ballot box of Turkey’s Kurdish minority, which aligned with liberals and secular Turks opposed to Erdogan’s leadership to win almost 13 percent of the vote, passing the legal threshold for earning representation in Parliament.
Selahattin Demirtas, 42, a former human rights lawyer who leads the largely Kurdish People’s Democratic Party, told reporters Sunday night: “As of this hour, the debate about the presidency, the debate about dictatorship, is over. Turkey narrowly averted a disaster.”
The Kurdish party opted to run a unified slate, rather than field independent candidates as it had in the past. But it was a big risk: either it would reach the 10 percent threshold and enter Parliament, or it would be shut out, and its seats would have gone to the A.K.P.
In the city of Diyarbakir, in the Kurdish heartland in the southeast, celebrations broke out as people flooded the streets, dancing and setting off fireworks.