President Boris Yeltsin has once again refused to compromise in the political crisis which threatens to be the most severe since he sent in the tanks to crush parliament in 1993.
Despite efforts to bring about a solution before the Duma votes on Mr Sergei Kiriyenko, his candidate for prime minister, Mr Yeltsin has indicated that he is not prepared to bend on the issue.
The key indicator on whether Mr Kiriyenko will get the Duma's approval tomorrow will be a procedural ballot on whether the vote on his approval will be taken in secret or openly in the Duma. The Communist Party, which has strongly opposed Mr Kiriyenko's nomination, announced yesterday that it will demand a roll-call ballot. Its leader, Mr Gennady Zyuganov, is understood to be worried that many of his deputies might ignore the whip if the vote is taken in secret.
The communists will be joined in demanding an open ballot by the Duma's only truly democratic grouping, Yabloko. A spokesman for this group told The Irish Times that if its demand for an open vote is met, it will impose an anti-Kiriyenko whip on its members.
Should a secret ballot be imposed, Yabloko would walk out of the chamber. Although this would virtually ensure Mr Kiriyenko's approval by the Duma, the Yabloko democrats believe that their protest will be a useful one.
Should the vote go against Mr Yeltsin and his protege tomorrow the result, paradoxically, will be to strengthen the President's hand. As Mr Kiriyenko's nomination has been thrown out twice, Mr Yeltsin will be obliged by his own constitution to dissolve the Duma and call elections if his choice is defeated a third time.
Much more importantly, a third defeat will allow the President to impose Mr Kiriyenko as prime minister after all democratic procedures have failed. This would leave Russia with no Duma for up to three months and allow Mr Yeltsin untrammelled powers over that period - a scenario which many anti-Yeltsin politicians fear even more than the installation of Mr Kiriyenko (35), a neophyte who arrived in Moscow from Nizhny Novogorod less than a year ago.
The constitution also states that should the president die in office or become incapacitated to the extent that he is unable to function as head of state, the prime minister will take over the presidency for three months before calling elections.
The prospect of such a completely untried politician taking over as leader of an unstable nuclear power has frightened many analysts, although most believe that the young and wealthy Mr Kiriyenko is at least capable of managing the Russian economy.
Mr Kiriyenko's candidacy received a boost yesterday when the orthodox communist grouping, People's Power, led by the former Soviet prime minister Mr Nikolai Ryzhkov said it would support him in tomorrow's vote.
Mr Yeltsin and his supporters are already virtually assured of the votes of the extremist Liberal Democratic Party, led by Mr Vladimir Zhirinovsky, known in western political circles as "Vlad the Mad". Mr Zhirinovsky and his party have consistently supported all of Mr Yeltsin's controversial measures to come before the Duma; they have an extra reason to do so on this occasion. With his party's popularity dwindling, Mr Zhirinovsky would face virtual political annihilation if early elections were called.
Most analysts yesterday predicted a narrow victory for Mr Kiriyenko in the crucial vote, though all of them felt that in the short period before the ballot the balance could swing dramatically one way or the other.