* Fewer economic spoils prompt fight among elite
* Signs multiply of tension within ruling class
* Kremlin tries to defend system
By Michael Stott MOSCOW, March 4 (Reuters) - As Russia's economy buckles under the global financial crisis, the biggest threat to the country's rulers may come not from mass demonstrations but from inside the walls of their own palaces.
Prime Minister Vladimir Putin and President Dmitry Medvedev, the ruling duo, face growing unrest from Russia's powerful business and political elite rather than from the passive, long- suffering populace, analysts and economists say.
Accustomed to lavish living and easy money during the country's 10-year boom which ended abruptly last autumn, the elite now frets that Putin and Medvedev will be unable to keep the economic pie big enough to go around.
Most economists expect the economy to shrink at least three percent this year, a big reversal from years of rapid growth. With budgets tight and reserves dwindling, the government has warned top businessmen not to expect big bailouts.
"Putin could have continued propping up his... Potemkin democracy for many more years if the petrodollars kept pouring in," wrote political analyst Dmitry Oreshkin this week, referring to the oil price boom which bankrolled Russia's prosperity.
"... But now the money is running out and it is frightening to consider the consequences."
In a country famous for keeping its political fights hidden, there has been an unusual rash of public remarks by prominent figures about tensions in the elite.
Gleb Pavlovsky, a Kremlin-connected political expert, broke a taboo with an interview in a mass-circulation newspaper by speculating about a possible coup against Putin from within.
"If we are talking about the sources of social protest in Russia, look for them in the corridors of power," he told the Moskovksy Komsomolets this week.
Kremlin press chief Natalya Timakova declined comment but the newspaper's official ties -- Timakova was its former Kremlin correspondent and her husband is a contributor -- mean the article was unlikely to have run without official approval.
On the same day, the Kremlin's political mastermind stepped out of the shadows to make a rare public speech rejecting the need for political reforms to combat the crisis.
Vladislav Surkov, first deputy head of the Kremlin administration, denied that the economic crisis threatened any kind of implicit pact under which the population had surrendered political freedoms to Putin in exchange for prosperity.
"I want to stand up in defence of the current political system," he told a forum in Moscow. "...there is no need to create the sentiment that if something changes for the worse in the economy, then that means a change of system."
Analysts said the fact that such a powerful figure felt the need to make a vigorous public defence of the political system -- saying in his remarks at least five times that everything was "fine" or "working well" -- showed the scale of the problem.
"Surkov's elite has been shaken, and he is very nervous," said liberal economist Yevgeny Gontmakher of the Institute for Contemporary Development, a think-tank which advises Medvedev.
"The situation inside the government is deteriorating."
The opposition New Times magazine published this week a confidential national poll of regional business and political elites which made worrying reading for the government.
Only a fifth fully supported Putin's policies and 60 percent said the concentration of power in the Kremlin under his 2000- 2008 presidency had damaged the government's effectiveness.
That contrasts with the mood among the population at large.
Two million Russians have lost their jobs and many more have seen salaries cut since the crisis but street protests have been muted so far and opposition parties have failed to benefit.
Lev Gudkov, director of the independent pollsters Levada Centre, explained this by saying the crisis had so far only directly affected about 10-15 percent of the population.
"The population's attitude towards those in power is starting to change gradually," he told Reuters. "But the political culture in Russia is one of passivity and patience, not going out into the streets."
Inside the corridors of power, concerns are growing about the stability and duration of the Medvedev-Putin ruling act.
Pavlovsky called in his interview for the pair to appear together more often in public to stop talk of cracks in their relationship.
Commentators say the two rulers, who worked closely together for nearly two decades, do not differ significantly on policy but the same may not be true of their respective teams.
"This fight (among the elite) is dangerous for both men," said Georgy Bovt, co-chairman of the opposition party "The Right Cause". "Their associates are not such good friends as they are and are quite capable of falling out."
"If either Putin or Medvedev left power, it would be a huge political crisis." (Additional reporting by Simon Shuster, editing by Janet McBride)