BAGHDAD, Iraq -- Iraq's parliamentary elections on May 12 might seem to offer more of the same because most of the leading candidates and movements have dominated the country's political life since the United States unseated Saddam Hussein in 2003. But the 44-year-old firebrand Shiite cleric Moktada al-Sadr is leading an encouraging transformation, which could jar Iraq's politicians out of their sectarian rut.
Mr. Sadr inherited millions of devoted followers from his family of revered religious scholars. Both his father and father-in-law were grand ayatollahs, the highest clerical level of Shiite Islam. He cemented his status by leading a bloody resistance against the American occupation and fighting the United States-allied government in Baghdad. He stubbornly defied foreign intervention, angering both Iran and the United States. He has purged corrupt operatives from his movement.
In the summer of 2015, Mr. Sadr made a potentially historic about-face, uniting with the Iraqi Communist Party and secular civil society groups who were protesting the government's failure to provide security against the Islamic State or even the basic necessities of life, including jobs and electricity. Together, the new alliance demanded an end to corruption.
Iraq regularly tops world rankings for corruption and suffers endemic unemployment, which is particularly high among youth. When oil prices were high, alleged corruption reached an epic scale, but the people did not receive any benefits in infrastructure, jobs or services. Even vital security services were gutted by no-show jobs, as glaringly revealed when there was no army on hand to stop the Islamic State's sweep through Mosul and Anbar Province to the gates of Baghdad.
Corruption has kept Iraqis poor and almost left the country at the mercy of the Islamic State. That is why Mr. Sadr's slogan "Corruption Is Terrorism" resonates with so many Iraqis. Frustrated with a decade of failures by the rulers in Baghdad, Mr. Sadr embraced civil society groups and their agenda: civic rights, better governance, fair distribution of resources.
An important outcome of Mr. Sadr joining a nonsectarian coalition is a new strain of pluralism and tolerance. The liberating effect is visible in how Iraqis irrespective of class, sectarian and sexual identities can reclaim public spaces without fear.
One spring morning, a group of young men in bouffant hairdos and burgundy and bright green three-piece suits hung out in Qishleh Gardens near Mutanabi Street, the historic gathering place of Baghdad's poets and intellectuals. In the local context, their attire announced them as gay men. As the men in colorful suits walked around, the clerics recruiting fighters for the Shiite Islamist militias nearby didn't even throw them a sideways glance.
In the afternoon, some of the men in colorful suits joined an anti-corruption demonstration led by supporters of Mr. Sadr. "We all want to put an end to corruption," said Mohamed Ismail, a 26-year-old unemployed day laborer. "We are all together."
Three years earlier, when demagogues loyal to Mr. Sadr were exhorting vigilante attacks on men seen as gay, the pairing would have been unthinkable. Back then, Iraq was riven by difference -- the sectarian-hued struggle between the Islamic State, which purported to speak for the Sunnis, and the governments led by Shiite Islamists, who claimed to represent the Shiite majority that had been oppressed under Mr. Saddam.
At the Baghdad Cultural Center, adjacent to the Qishleh Gardens, smiling volunteers from Mr. Sadr's organization distributed fliers with his pronouncements. "Our new goal is to start an independent technocratic government," said Majid Hamid, a 26-year-old volunteer. "We have no problem with anyone who is Iraqi." The movement's emphasis is now on civic questions.
After more than a decade of dominance by Islamist Shiite movements, competitors for power can no longer meaningfully distinguish themselves by their sectarian identity. Self-styled religious parties have been implicated in every major graft scandal, including the mishandling of oil revenue and defense contracts.
In early May, Grand Ayatollah Ali al-Sistani, the most revered cleric in the country, took the unprecedented step of declaring that true believers must not vote along sectarian lines and reminded voters that the clergy has not endorsed any party.
The biggest transformation of all has come during the fight against the Islamic State, which united all manner of Iraqis against nihilist fundamentalists: Shiite and Sunni, Kurd and Arab, Muslim and Christian, religious and secular. Every major electoral faction includes a mix of Iraqis, and the ideas of nationalism and secularism are slowly returning to the Iraqi political sphere.
Prime Minister Haider al-Abadi, who has roots in the secretive Shiite Islamist Dawa Party, has positioned himself as a nation-builder who thwarted challenges from Sunni supremacists and Kurdish separatists but is willing to accept any patriot as a member of his coalition. Even the most militant Shiite militias have included Sunni partners in their electoral coalitions, including the Fatah Alliance, led by Iran's fearsome ally, Abu Mahdi al-Muhandis.
Mr. Sadr has ordered his followers to support the idea of a secular, nationalist government run by "technocrats," experts who are not career politicians and supposedly will be able to solve Iraq's ills. He touts the importance of the rule of law and civilian power.
In a series of interviews with politicians, analysts, fighters and citizens, I repeatedly heard that a broad range of Iraqis believe they are at the beginning of a "nationalist moment," when the country's political culture might be transformed for the better.
Mr. Sadr has reinvented himself countless times in an erratic political career and can be a fair-weather ally. His appreciation for new, secular allies is not an endorsement of liberalism or progressive views.
But Mr. Sadr has always been a nationalist, committed at least in rhetoric to unifying patriotic Iraqis regardless of sect or ethnicity. His current campaign for a civil, anti-sectarian, reformist government raises hopes and possibilities not experienced in recent Iraqi history. He is changing the terms of political debate.
His political lieutenants say they want to lead the Iraqi government, or else serve as a vigilant parliamentary opposition. Since 2003, every faction that won a share of votes opted to join a broad coalition government and extract its share of the spoils from the public sector trough.
Mr. Sadr shows that a political movement known for the exploits of its militia and corruption can also become a standard-bearer for root-and-branch political reform. His unlikely reformist alliance could give Iraq's political culture the jolt it needs.
Thanassis Cambanis, a senior fellow at The Century Foundation, is the author, most recently, of "Once Upon a Revolution: An Egyptian Story."