Dubai, United Arab Emirates: In just three years, Iraqi Prime Minister Haider al-Abadi has rebuilt the army, defeated Islamic State and restored sovereignty across a deeply divided nation.

Still, as he is quick to warn in weekly addresses to the nation, stability remains fragile.

The country is coping with an ever-bubbling threat of violent sectarianism between the Shiite and Sunni Arab populations - as well as endemic government corruption and overwhelming economic despair, especially among millions of citizens left homeless after the battles against IS.

This is a crucial moment for Iraq, as it gears up for an election that could unravel its hard-fought gains. The vote could also reshape the influence of Iran across the Middle East and determine the likelihood of an IS resurgence.

But it's an important moment for Abadi, too. He has never spearheaded an electoral campaign, and has already stumbled ahead of a vote that will test his own political acumen in a challenging security environment.

Two weeks ago, for example, before the deadline to register for the May 12 elections, Abadi welcomed the leaders of Iranian-backed Shiite militias into a grand coalition that he hoped would cement his image as a moderating figure who could reach beyond his own Shiite base to appeal to Iraq's other communities.

Iraq's Shiites, although the majority, are fractured into competing political parties. Since Saddam Hussein's overthrow in 2003, Shiite coalitions have run the government, a formula still considered key in this election.

The backlash to Abadi's move was swift.

The Iranian-backed militias have won praise for helping defeat IS, but they have also been accused in sectarian atrocities and their leaders are seen by many as tools of Iran. Sunni and Kurdish leaders were furious. Even a Shiite leader, Muqtada al-Sadr, a possible kingmaker in this vote, called the alliance "abhorrent".

Within 24 hours, Abadi had reversed himself, and the militia leaders left the coalition.

Abadi's blunder was a stark reminder of the fact that, with the election still more than three months out, nothing can be taken for granted.

While he is still Iraq's most popular politician and front-runner, Abadi's clumsy outreach and deal-making have compounded his difficulties, alienating the influential factions he needs to win.

"Abadi has a narrow line to walk," said Renad Mansour, an Iraq analyst at Chatham House. "He is popular among many types of Iraqis, but he also has serious enemies. Politics is about shared power in Iraq."

Abadi took power in 2014, shortly after the devastating IS blitzkrieg occupied one-third of Iraq and enslaved tens of thousands of his countrymen. Most Iraqis attribute that disaster to the failings of his predecessor, Nouri al-Maliki, who ruled for eight years before being ousted by his own Shiite coalition in favor of Abadi.

But while Abadi is the leader of the nation, he does not head his own political party, the Dawa Party, making his political position precarious. The party's leader remains Maliki, who despite his chequered political past is itching for a comeback.

So in a classic example of the serpentine nature of Iraqi politics,  Maliki has blocked Abadi from using Dawa Party resources for his campaign.

Abadi created his own coalition, the Victory Alliance, to which he first welcomed, then hastily removed, the pro-Iranian militias. The coalition immediately attracted dozens of national and regional politicians from across sectarian lines, giving his aides confidence in a strong platform to enter the election season.

Iraq's postwar political realities have reserved the position of prime minister for a Shiite. Given the country's history of tight elections and coalition governments in the three national polls since 2003, Abadi needs an alliance with at least one of three major bulwarks of Shiite political power to win, analysts say. (The largely ceremonial presidency is held by a Kurd, and the speaker of parliament is a Sunni.)

The problem is that these Shiite powers all have their own baggage. One is Maliki, a politically damaged rival who wants the PM's job himself. Another is the pro-Iranian militia leaders, who are close to Iran's Revolutionary Guard, a liability that has already backfired on Abadi.

And the third is  Sadr, a populist firebrand who has become a champion of the poor and unemployed and a fierce opponent of Iranian meddling.

Sadr, best known to Americans as the militia leader who for years after the US-led invasion fought and killed coalition troops,  is running his own coalition which, like Abadi's, is cross-sectarian. It includes Sunni leaders who welcome Sadr's anti-Iranian message.

Politicians close to Abadi had been in exploratory talks with Sadr's followers about joining with them in a possible coalition. It is not clear why those talks foundered, but Sadrists say their leader was angered by  Abadi's alliance with the pro-Iran militia leaders.

Registration for the election ended on January 15.

"We did not have time to finalise who our main partners would be, what we stand for and what we all agree with," said Ali al-Adiib, an MP close to Abadi. "We are discussing all these things now."

Some analysts say Abadi's reputation may be forever tarnished.

"The latest developments undermine the view in Washington that Mr Abadi is a bulwark against sectarian forces with strong links to Iran," wrote Hassan Hassan, a counter-terrorism author, in an opinion piece published in Abu Dhabi-based newspaper The National.

Others say it's too early to make predictions this far in advance given Iraq's unpredictable security climate.

One way that Abadi could bolster his reputation, especially among Iraq's Sunnis, is a successful performance at an international donors' conference next month in which his government is hoping to attract hundreds of billions of dollars in aid to rebuild the mostly Sunni cities destroyed during military operations against IS.

The United Nations estimates that around 2.6 million Iraqis, mostly Sunni Arabs, remain displaced after the utter devastation of their home towns.

Leading Sunni and Kurdish MPs argued last week to delay the election, saying that a fair vote would be impossible because so many Iraqis were still scattered and their regions lacked the infrastructure for a vote.

On January 21, Iraq's Supreme Court ruled that a delay would be unconstitutional.

Wathiq al-Hashimi, the head of the Iraqi Group for Strategic Studies, believes that, despite the challenges, Abadi has the best chances of victory for a simple reason: the optimism he restored to Iraqis after beating back IS.

"The path for Abadi's second term will be one strewn with flowers," he said.

New York Times