By Richard Galpin
BBC News, Novosibirsk, Russia
Officially Russia's presidential election campaign is not due to start until December, but in effect it has already begun.
Deputy PMs Medvedev (left) and Ivanov are seen as likely rivals
Top business leaders and politicians from many countries met in St Petersburg at the weekend with the question of who will succeed President Vladimir Putin high on their agenda.
Mr Putin, who has been in office since 2000, is required by the constitution to step down after elections due to be held early next year.
Among the high-profile speakers at the St Petersburg Economic Forum were the two men currently seen as the frontrunners in the race to become the next Russian president - the first deputy prime ministers, Sergei Ivanov and Dmitry Medvedev.
In the spotlight
In recent months both Mr Ivanov and Mr Medvedev have travelled across Russia on a series of highly-publicised trips.
It is all being carefully choreographed by the Kremlin.
President Putin seems to be testing out his two favourites, seeing how they perform and how the public reacts to them.
Mr Ivanov and Mr Putin, both ex-KGB, are close associates
It is widely expected that later this year Mr Putin will nominate one of them - or any other candidate who may emerge before then - as his preferred successor.
And all the experts agree that whoever gets Mr Putin's official seal of approval will win the election because the electorate will follow Mr Putin's lead.
In February Mr Putin moved Sergei Ivanov from his position as defence minister, making him first deputy prime minister.
The promotion has been widely interpreted as indicating that Mr Ivanov is now the frontrunner in the presidential election race.
Kremlin chess game
"He's got a good chance," say Mikhail Fishman of the Russian Newsweek magazine. "The common perception in the elites is that he's already the winner. I would say he is one or two steps ahead of Mr Medvedev. But the game is not over yet."
We were given a rare opportunity to accompany Mr Ivanov on one of his "campaigning" trips to southern Siberia.
With a police escort we swept out of the city of Novosibirsk to attend the 50th anniversary celebrations of the prestigious regional academy of sciences.
Mr Ivanov (centre) toured an elite Soviet-era scientific centre
The academy is part of what used to be a top secret scientific research complex.
Mr Ivanov as guest of honour was given full celebrity status.
But surprisingly for a senior politician he looked stiff and awkward as he stood centre-stage in the full glare of the spotlights, handing out medals to the academy's most illustrious members. Like President Putin, Mr Ivanov has a frosty, rather grey demeanour.
Secret service career
The two men are remarkably similar.
They are the same age, come from St Petersburg and worked for the Russian intelligence agencies before entering politics.
In the late 1990s, when Mr Putin was director of the internal intelligence agency the FSB, Mr Ivanov was appointed as his deputy.
They are believed to be close.
Despite Mr Ivanov's lack of panache, some scientists at the academy near Novosibirsk seemed impressed.
"He'll be an excellent president," says Igor Zhimulev, Professor of Genetics.
"I could repeat what Henry Kissinger said - that all the best politicians come from intelligence."
Prof Zhimulev also favours Mr Ivanov because as deputy prime minister he has been given special responsibility for science and technology as well as the military-industrial complex. And already he says scientists have seen big increases in their salaries.
But it was Mr Ivanov's intelligence training which was on show later when we tried to pin him down on his presidential ambitions at an impromptu news conference.
He fixed me with a cold, hard stare and demanded I translate my question from English to Russian.
"I'm sorry, I have an iron rule," he said in fluent English, "in Russia I only speak in Russian."
He went on (in Russian) to dismiss any talk of running for president, saying he could not think about this now as he had enough to do in his new job as deputy prime minister.
With that he walked off, leaving his aides to chastise us for our impertinence.
Russian politicians have grown accustomed to a deeply compliant media.
To outside observers the prospect of another Russian president who hails from the secret services is troubling, particularly given the kind of signals coming from Mr Ivanov.
"He's showing essentially who's behind him, who his main contacts are in the ministry of defence and the defence industries," says Rose Gottemoeller, director of the Carnegie Endowment for International Peace in Moscow.
"These are the tough guys, these are the Russian hawks and they have been since Soviet times. And he's clearly showing he really has that group working behind him."
But while Mr Ivanov may be instinctively hawkish and authoritarian, some analysts believe he is an unknown quantity as a politician because until now he has strictly followed his mentor President Putin.
"The question is, who is Mr Ivanov?" says Mikhail Fishman of Russian Newsweek magazine. "At first (if he's elected president) he would follow the same line as Mr Putin, but then he would change and no one can say what would be next."