Hassan Rouhani's first-round success in the Iranian elections has sent an strong message to the regime.

On the face of it, the process went well. Having ensured that the list of candidates was not going to offer any existential threat to the system, Ayatollah Khamenei needed to ensure that this election went smoothly and with a good turnout. With a voter turnout of over 72% and a general feeling that the voting process was free and fair, that aim was achieved.

But the strong win by Hassan Rouhani (pictured) in the first round of voting was not part of the script. Rouhani ended up serving as a lightning rod for the four years of discontent the Iranian public has felt since the widely condemned 2009 elections. The backing of former presidents Rafsanjani and Khatami three days before polling and the tactical withdrawal of Muhammad Reza Aref, the only other 'moderate' candidate, also energised Iranian voters to believe that their discontent with the system could be registered by voting.

The fact that Rouhani garnered over 50% of the vote has also sent a strong message to the regime that the social and political status quo is not welcome. For their part, the conservative candidates did not help their cause by remaining divided throughout the first round.

The election of Rouhani offers the possibility of a much-needed circuit breaker, both domestically and internationally. During the presidential debates Rouhani spoke about social liberalisation, but not to an extent that confronted the regime. He is also a Western-educated polyglot and former chief nuclear negotiator under then-president Khatami who will present a worldlier visage to the West.

However, his electoral stance as a moderate should not disguise the fact that he is a believer in the political system of the Islamic Republic.

Moreover, so entrenched and opaque is the decision-making process on the really important foreign policy issues in Iran that nobody really understands what influence he will have on the Supreme Leader's calculations on issues such as the nuclear program. But the size of his electoral victory will give him some authority to ease social restrictions and could give him a freer hand to select his cabinet.

The Supreme Leader and his close circle will likely give Rouhani some latitude early on, however Rouhani's close relations with Rafsanjani and Khatami will mean that the Supreme Leader will want to circumscribe Rouhani's powers so that he doesn't present as an alternative seat of power to the Supreme Leader and his close backers such as the Revolutionary Guard.

Given the parlous state of the economy, the impact of a tightening sanctions regime and the limitations on his executive powers, Rouhani's presidency is likely to be more about a change in style and less about substance. He is also aware that half the Iranian population voted for conservative candidates, so he must be careful with any liberalising moves he makes.

But as Rouhani would be aware, at this juncture stylistic changes will send a welcome message to the regional and international community. While the international community will be looking at issues such as nuclear negotiations and the ongoing civil war in Syria to judge Rouhani's ability to make Iranian policy less confrontational, the reality is that, while he is well versed in both issues and he can make his feelings known to the Supreme Leader, they are not under the purview of the president. Domestically he will ultimately be judged on the economy and to a lesser extent any social liberalisation.

Rouhani has been elected with a large popular mandate, but he will work within a system in which his ability to initiate and manage change are quite circumscribed. Domestic and international expectations should thus be tempered. But if he is able to change the tone from Ahmadinejad's aggressive confrontational style, that will be an achievement in itself.

Photo courtesy of Wikipedia.