A stunning victory:A billionaire has unexpectedly won Georgia’s elections

Bidzina Ivanishvili made a bold promise a year ago. Georgia’s richest man promised to assemble a coalition to win the parliamentary elections in 2012 and unseat the “dictatorship” of President Mikheil Saakashvili. On October 1st Mr Ivanishvili’s Georgian Dream coalition won 55% of the vote. Mr Saakashvili gracefully conceded that his United National Movement (UNM) had lost, and welcomed Mr Ivanishvili into power.

But not just yet. Georgia remains a presidential republic for another year, when constitutional amendments take effect. Until then Mr Ivanishvili’s scope will be limited. He called for the president to resign at once, then rescinded. Mr Saakashvili is not budging. The coming months may be bumpy.

Despite the bickering, the election is a landmark. Never in Georgian history has a government changed so peacefully and lawfully.

How Mr Ivanishvili’s disparate coalition will deal with this legacy is unclear.  His main policy is better relations with Russia. It defeated Georgia in a short war in 2008 and occupies a fifth of its territory: the self-proclaimed states of Abkhazia and South Ossetia. A change of personality at the top should make a thaw easier. Vladimir Putin, the Russian president, once said he wanted to hang Mr Saakashvili “by the balls”.

The cause of the row was Georgia’s pro-Western orientation: its bid to join NATO was anathema to Russia and regarded with deep scepticism in much of the alliance. Mr Ivanishvili says he too wants to support membership of the alliance. His first trip abroad may be to America. But the new premier’s real priority will be to revive trade with Russia. Kremlin sanctions have strangled Georgian exports such as wine, fruit and mineral water.

Mr Ivanishvili said during the campaign that Mr Saakashvili and his officials would face unspecified “justice” once Georgian Dream came to power. Among other wild talk, he suggested that any supporter of Mr Saakashvili’s was an “accomplice in the cruellest crime”. Even the election result is open to challenge. Mr Saakashvili’s UNM claim that Georgian Dream activists are pressing local election commissions to change results in their favour. The NATO observation mission in Georgia has expressed “serious concern” about that.

It is all still fragile. But by admitting defeat, Mr Saakashvili handed his country a victory and wrong-footed Mr Ivanishvili, who had said that he would never be allowed to win elections. Now that he has, he has a great responsibility to the system that has vaulted him to power.