ISTANBUL — Iranian presidential hopeful Mohammad Bagher Ghalibaf withdrew Monday from the race to unseat the country’s moderate leader in a move to unite conservatives behind fellow hard-liner Ebrahim Raisi in the home stretch for Friday’s election.
The two candidates were the top conservative challengers to President Hassan Rouhani, a pragmatist whose government negotiated a 2015 deal with world powers to rein in Iran’s nuclear program in exchange for lifting international sanctions.
Ghalibaf and Raisi, who were polling neck and neck, seized on widespread discontent about the slow-growing economy. Although sanctions relief has allowed oil exports to resume, the limited growth has not significantly improved the lives of ordinary Iranians.
Ghalibaf campaigned on job creation and boosting cash subsidies. But his withdrawal Monday solidified Raisi’s status as the front-runner for conservatives, who have struggled in past elections to coalesce around one candidate.
Recent polls put Rouhani with a comfortable lead over Raisi, but such surveys are unreliable in Iran, which limits political activity and free expression.
‘‘I ask my supporters throughout the country to use all of their potential’’ to elect Raisi, Ghalibaf said in a statement carried by state media.
The promise of Iran’s 1979 Islamic revolution ‘‘can only be achieved by changing the status quo,’’ Ghalibaf said. He called a vote for Raisi a ‘‘crucial decision’’ to ‘‘preserve the unity’’ of the revolution.
Ghalibaf’s withdrawal ‘‘was likely an orchestrated move to shore up support behind a single principlist candidate, and pose a potent challenge to Rouhani,’’ said Behnam Ben Taleblu, an Iran analyst at the Foundation for Defense of Democracies, a conservative think tank based in Washington. Iran’s hard-line conservatives are widely known as ‘‘principlists.’’
‘‘Iran’s political right has been scrambling to field a single candidate that could push back against’’ Rouhani’s coalition of technocrats, pragmatists, and reformers, Taleblu said.
Although Rouhani was expected to easily secure a second term, ‘‘it is highly likely that Ghalibaf’s voters will flock to Raisi,’’ Taleblu said.
Raisi, a 56-year-old Shi’ite cleric, has close ties to Iran’s supreme leader, Ayatollah Ali Khamenei, who last year appointed him as head of Iran’s largest charitable foundation, the Astan Quds Razavi.
He served for years on the judiciary, including on a 1988 panel accused of sentencing thousands of political prisoners to death.
But he has limited political experience and gave weak performances in three televised presidential debates.
His links to Iran’s powerful Revolutionary Guard Corps and hard-line ruling clerics could push undecided voters to the Rouhani camp. Rouhani, 68, is also a Shi’ite cleric.
‘‘So far, Raisi has received support from the shadowy corners of the Iranian security establishment,’’ Taleblu said. But he ‘‘has failed to touch off a national movement.’’