By Dominic Evans and David Dolan
ISTANBUL (Reuters) - Tayyip Erdogan's shock announcement of snap elections in June has caught Turkey's troubled opposition off guard and brought him within reach of his cherished goal, a powerful presidency with sweeping executive powers.
The elections will finally trigger Turkey's switch from a parliamentary to a presidential system, a transformation Erdogan narrowly won in a hard-fought referendum a year ago.
That vote was held, as the June 24 parliamentary and presidential elections will be, under a state of emergency which Turkey's allies including the United States say raises questions over their integrity.
A masterful campaigner, Erdogan has won nearly a dozen elections and dominated Turkish politics since his Islamist-rooted AK party swept to power in 2002. He remains Turkey's most popular politician, admired by millions for championing the pious Muslim working classes and delivering airports, hospitals and schools during a period of strong economic growth.
His opponents are ill-prepared to challenge him.
Nine members of the pro-Kurdish HDP party have been jailed or detained pending trial, the main opposition CHP has yet to choose a presidential candidate, and the breakaway nationalist Iyi Party has only been in existence for a few months.
Announcing the elections on Wednesday, Erdogan said Turkey needed to switch quickly to a powerful presidency to confront economic challenges and the war in Syria.
Those two factors support his decision to go early. Economists don't expect Turkey to sustain last year's breakneck growth of 7.4 percent through to the scheduled Nov 2019 poll date, while Erdogan is enjoying nationalist acclaim for early military success across the border in Syria.
"Erdogan has all odds stacked in his favor. From ... economic growth to the state of emergency which he has been using to crack down on opposition, to a near complete control of the media," said Soner Cagaptay, a fellow at the Washington Institute.
The prize for the victor in June will be power almost unprecedented since the Turkish republic was created under Mustafa Kemal Ataturk, out of the ruins of the Ottoman empire nearly a century ago.
"The office of prime minister will cease to exist. Erdogan will become head of state, head of government, head of the police, head of the army and head of the ruling party," said Cagaptay. "He will become the most powerful Turkish leader since Ataturk, and in some regards more powerful."
The proposed powers were criticized by a leading European rights body, the Council of Europe, which said at the time of the referendum that the changes risked consigning Turkey to authoritarian rule.
"What Turkey needs is a progressive constitutional democracy whose branches of government are actively involved representing the interests of its people," said David Phillips, Director of the Program on Peace-building and Rights at Columbia University.
"That's not served by the new constitution which establishes the president as the primary purveyor of all powers."
Erdogan says Turkey needs strong leadership to steer it through security challenges including confronting a network Ankara blames for a failed 2016 military coup, the war in Syria, and militant threats inside Turkey.
Government spokesman Bekir Bozdag, defending the move to the new executive presidency, said the current system of mixed parliamentary and presidential rule was slowing the country down and the change would mark "the opening of a new era".
He said early elections "will give great impetus to the economy, lift uncertainties and increase investments".
Despite government denials, speculation about early elections had swirled in Turkey for months. But few anticipated they would happen as soon as June.
Erdogan had a "menu of options" in front of him, said Aaron Stein, senior fellow at the Washington-based Atlantic Council, including sticking to the November 2019 date or holding polls in July or August of this year.
"He ultimately decided on the nuclear option on the menu in front of him ... because it would be the most effective for him to be elected," Stein said.
Hours after Erdogan made his announcement, parliament voted to extend the state of emergency for another three months, which will cover the campaign and the vote.
Since emergency rule was first imposed following the failed 2016 military putsch, 160,000 people have been detained, the United Nations said last month, accusing Ankara of mass arrests, arbitrary sackings and other abuses.
The United States, an ally and NATO partner whose ties with Turkey have frayed badly over the last year, voiced concerns over the elections.
"During a state of emergency, it would be difficult to hold a completely free, fair, and transparent election," U.S. State Department spokeswoman Heather Nauert said this week.
The pro-Kurdish People's Democratic Party (HDP) has seen 11 of its 59 lawmakers stripped of their parliamentary status. Nine are in detention, and the party says the election will be held with the country in a "war psychology".
"We are entering the elections under a state of emergency and in an atmosphere where the media is censored," spokesman Ahyan Bilgen said, referring to the scant television air time given to opposition party rallies in last year's referendum.
The new Iyi (Good) Party, led by former interior minister Meral Aksener, will put forward candidates for parliament but authorities have yet to rule on whether it has met requirements to stand. Aksener says she will run for president.
The CHP party says its leader Kemal Kilicdaroglu is unlikely to run because it believes an elected president should not be the leader of a political party.
Opposition parties have also criticized revisions to election regulations that will allow ballots that are not stamped by the local electoral board to be deemed valid, a move they say encourages electoral abuse.
The government says voters still need proof of identity and that votes will be counted in front of party representatives, preventing fraud. "You cannot rig it," Erdogan's spokesman Ibrahim Kalin said this month.
Erdogan's AK Party is confident of victory, saying its latest opinion poll suggested he enjoys 55 percent support. But many fear this time, an Erdogan victory will cement a lasting one-man rule in Turkey.
"It's terrible news for Turkey because Erdogan has almost no graceful exit left," Cagaptay said. "His only exit is to keep winning, winning, winning elections."
(Additional reporting by Gulsen Solaker and Ece Toksabay; Editing by Giles Elgood)