Iraqi Shia leader Muqtada al-Sadr and his Sairoon coalition have now been confirmed as the winner of Iraq's parliamentary elections with 54 seats. The closest runner-up is Hadi al-Amiri's Fatah list which has obtained 47 seats.

These results have already imposed a new dynamic, which will have an impact on the country's domestic and foreign policy. The full extent of any reforms will depend on a number of factors, some of which will play out in the coming months.

Political fragmentation
While Sadr's 54 seats translate into only 16.4 percent of the seats in the new parliament, Iraqi politics are now so fragmented that the importance of his share is significantly amplified. In previous years, formation of governments of national unity which brought together almost all of the parties that had representation in parliament was customary in Iraq, yet this will no longer be possible today for a variety of reasons.

Despite an electoral law that was designed to benefit larger coalitions, the next parliament will accommodate 28 parties that have 5 seats or less. Together these parties will occupy a total of 58 seats (or around 18 percent of the next parliament).

Iraq's Sunni community is also impossibly splintered. Ten different Sunni parties will be represented in the next parliament and will occupy a total of 39 seats. It will be close to impossible to incorporate most if not all of these MPs in the next government, given that their respective political weight may not be worth the cost that would be incurred by including them.

The parliament's remaining seats are also not equally distributed. Only three electoral alliances returned between 40 and 60 seats. An additional three alliances have between 20 and 40 seats. In that context, it is almost inevitable that the next government will include all three of the main alliances including Sadr's Sairoon alliance.

In addition, despite the relatively minor difference between them (in 2014, there was a 58 seat difference between the winner and the closest runner-up), not all of the three major political alliances are created equal. Sadr is one of the only political figures who enjoy consistent and ever growing support among a specific constituency. In 2016, his supporters even stormed the Green Zone and ransacked the parliament building.

As a result, his alliance is far less susceptible to splintering and to floor-crossing. Sadr's closest competitors are temporary alliances of convenience that are likely to be reduced in the coming months and years.

Iran's interests at stake
All of the country's main political forces appear to understand the new political and numerical realities that the elections have imposed and are now gravitating towards Sadr's pole. A number of bilateral meetings have already taken place since the preliminary results were announced, many of which have involved senior leaders paying a visit to Sadr on his terms. Sadr is now in prime position to extract concessions and to impose part of his agenda. Given how aggressive he has been in the past, that is unlikely to please many actors.

Unsurprisingly, many Iranian officials are said to be displeased with the electoral results. Iran's interests and influence were an important issue during the electoral campaign and will continue to be during the government formation process. Iranian influence is, in fact, one of the only substantive points of divergence between Iraq's main parties.

Sadr insists far more than many of his rivals on an 'Iraq first' approach, which some interpret as a call to exclude Iranian interests from policy considerations.

Iran has significant influence in Iraq but it is far from the all-controlling behemoth that some analysts claim it is. More than a decade ago, Iran encouraged all of the country's main Shia parties to close ranks in a single electoral alliance and also encouraged the formation of a mechanism to allow the parties to work out their differences behind closed doors.

These parties did not follow the script. They failed to improve security, participated in deepening corruption while simultaneously competing with each other for leadership, causing the alliance to fall apart in 2009.

Iran responded by modifying its principle objectives, which today appear to be to ensure the formation of a government that maintains friendly political, security and economic relations with Tehran. In 2014, it calculated that then Prime Minister Nouri al-Maliki was best placed for that purpose, but was unable to keep him in government. It opposed Haider al-Abadi's appointment as prime minister.

Perhaps most importantly, Iran is very aware that many Iraqis are suspicious of foreign interests in their country. For that reason, Iran seeks to maintain influence through accommodation and deliberately avoids confrontation for fear of a backlash.

In practical terms, what that means today is that Iran will likely seek to establish some or all of its main allies (mainly the Fatah and State of Law coalitions, who together have 72 seats) as a strong united voice in the next government.

Sadr's agenda
Sadr's policy agenda is hard to distinguish from that of his main rivals. Almost all of the election's candidates focused their campaigns on the need for reform, improved standards of living, anti-corruption measures, etc. Sadr insists far more than many of his rivals on an "Iraq first" approach, which some interpret as a call to exclude Iranian interests from policy considerations. That and the fact that many of his supporters are fond of chanting anti-Iranian slogans at demonstrations has raised concerns in Tehran.

But just as the Iranians cannot control who will occupy the prime minister's position, they are also fully aware that Sadr's options are equally limited. He may be in pole position, but he cannot fully exclude both Fatah and the State of Law coalitions from the next government. That would be interpreted as a deliberate and explicit snub against Iran's interests, which would invite an equally strong response. And Sadr would rather avoid direct confrontation with Iran.

Both of these dynamics will play themselves out in the government formation process. As always, most of the focus will be on the "sovereign" ministries (defence, interior, foreign affairs, finance, etc), and Iran's allies are likely to demand control over at least one of the security portfolios.

The next parliament will be the first in which none of the main candidates for the prime minister's position is backed up by a dominant electoral alliance. The premiership will continue to be an important position; through it and with the support of the cabinet's key staff, individual politicians will be able to exercise significant control over state policy.

Sairoon does not have many frontrunners for the prime minister's position, which has led to speculation that Sadr will allow for incumbent Haider al-Abadi to stay on. Regardless of whether that happens, Sadr will likely turn his attention to how the office of the prime minister functions. That will likely include gutting the prime minister's office of its staff, which has been dominated by former prime minister Nouri al-Maliki's Islamic Dawa party since 2005. New officials are likely to be recruited, who will seek to impose a new agenda for both the prime minister and the cabinet of ministers.

If Sadr is genuine in wanting to curb foreign influence, and if he plays his cards right during the government formation process, then he may find that he will have sufficient leverage to do so; but this is far from a given. The coming period of negotiations will reveal what his true goals are and how adept he is at achieving them.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial stance.