RIZE, Turkey – Beaming down from a three-story-high red banner over a main shopping street, the local boy who rose to the heights of power, Recep Tayyip Erdogan, urges the residents of this Black Sea town to "come on, lay claim to your president."

For more than a decade, Erdogan, 61, has been the dominant political figure in this country of nearly 80 million, first as prime minister and since August as president. Sunday's general elections will determine whether the man already accused of autocratic rule becomes still stronger.

Should the right-of-center, pro-Islamist Justice and Development party he founded win an absolute majority in the 550-seat Parliament, it intends to amend the constitution and turn his figurehead post into a more powerful American-style presidency.

But the "claim your president" banners, seen in many places around the town where Erdogan was born, offer signs that he has jumped the gun.

These are parliamentary elections and he's not on the ballot. Under the current constitution, he's supposed to be politically neutral, so every poster linking him with the vote or with Prime Minister Ahmet Davutoglu, every public appearance in which he takes sides, adds to the case his opponents are making that he has violated the constitution.

But Erdogan has turned this into a referendum on himself. And while there's almost no chance his home region will vote against him — in 2011, it returned three members to Parliament from his party, known by its Turkish initials, AKP — the race here provides indications why the country may hold back from giving him the supermajority needed to revise the constitution.

Unhappiness over the country's uneven economic development and disquiet over a corruption scandal that Erdogan has done his best to suppress motivate his opponents.

Kurds could be spoilers

Chief among them is the Kurdish People's Democratic Party, or HDP, which is running in national elections for the first time and can upset the Erdogan applecart if it receives 10 percent of the vote and enters the Parliament.

Two blasts ripped through an HDP rally on Friday, killing two people and injuring more than 100 in what Erdogan described as a "provocation" designed to undermine peace.

Erdogan's critics here are cowed, but they still speak out.

"People here don't read. They don't think. We don't have jobs. But still they give their votes to Tayyip. They are stupid," said Emel Igrek in a random street interview.

A group of about five middle-age men listened and took offense. "You call us stupid? Take back your words," said one, as the group advanced toward her.

Ismet Civelek's praise for Erdogan was straight out of the party talking points. "He's the charismatic leader, a man of international political influence," he said.

As Turkey's most powerful leader since Mustafa Kemal Ataturk, who founded the republic in 1923, Erdogan doesn't take criticism kindly. While claiming to advance democracy, he has stifled dissent, used his powers to suppress media freedom, repeatedly clamped down on social media and further undercut Turkey's weak judiciary.

Faced with a corruption scandal, he reassigned prosecutors, judges and police by the hundreds and mounted a vendetta against Fethullah Gulen, a U.S.-based Islamist scholar with a following in the Turkish police and judiciary, accusing him of creating a "parallel state."

Ten months as president have not diminished Erdogan's street-fighter instincts. Last week, he was on the offensive, saying of the leaders of the other parties that "lying has become their character," starting a criminal suit against the editor of one of the few independent news outlets.

But he wouldn't agree to a debate with the other parties, rarely does news conference and talks mostly to government-friendly news outlets.

Scandal over excesses

Despite opposition party efforts to highlight the scandal, leaders of Erdogan's AKP, using their absolute majority in Parliament, have suppressed the debate. But Erdogan's excesses, including construction of a 1,150-room presidential palace in Ankara, cannot be covered up. When opposition leader Kemal Kilicdaroglu accused Erdogan of installing gold-plated toilet seats, the president filed a libel suit against him.

Any follower of Gulen has all the more reason to vote for another party. Enver Ak, the owner of a dry cleaning shop, said that "people were content with Erdogan's image as a tough guy, but now he's gone too far." Erdogan's attitude is "you're either with me or against me," he said. As for the corruption scandal, he said, "This is what changed people's views about the AKP."

Ak said the best alternative he could see for now is the Republican People's Party, or CHP, the left-of-center party founded by Ataturk, which dominated Turkish politics for more than seven decades.

If HDP fails to enter Parliament, the AKP will probably take most of votes and could acquire a majority — probably not the two-thirds needed to approve a new constitution in Parliament alone, but quite possibly the three-fifths needed to put a new constitution to a national referendum.

The unstated message is that the Kurdish HDP, if elected, will put a brake on Erdogan's accretion of power and perhaps even force a coalition government.

"This is a common understanding: If you hate Erdogan, you should vote HDP," said Behlul Ozken, who teaches international relations at Marmara University.