President Vladimir Putin chose a little-known government official to become Russia’s new prime minister Wednesday, a surprise move that set off fevered speculation over whether loyal technocrat Viktor Zubkov was being groomed to replace Putin next spring.

The move came a few hours after Putin dissolved the Cabinet of his long-serving prime minister, Mikhail Fradkov, saying he needed to appoint a government better suited to the election campaign and to “prepare the country” for life after the elections.

The nomination of Zubkov, who has overseen investigations into suspicious financial transactions, caught much of the political elite off guard, which appeared to be Putin’s intention.

Most observers said they did not see Zubkov as Putin’s successor, but rather as a caretaker prime minister, perhaps to be replaced closer to the March presidential vote. Others said they considered his appointment a signal of Putin’s intention to retain control after he leaves the presidency.

In promoting Zubkov, whose nomination could be approved by the lower house of parliament as soon as Friday, Putin showed he is still calling the shots.

The plucking of Zubkov from relative obscurity reminded many Russians of Putin’s own ascension to power, which began when former President Boris Yeltsin suddenly named him prime minister in August 1999. After the Kremlin secured control over the lower house of parliament in elections the following December, Yeltsin again shocked the nation by stepping down on the last night of the year and naming Putin acting president.

“Here the entire nation is trying to guess who Zubkov is _ a technical prime minister or something else? It was the same situation with Putin,” said Boris Nadezhdin, a leader of the liberal Union of Right Forces party.

Some speculated Zubkov would succeed Putin as a caretaker president, allowing Putin to return in 2012 or sooner. Zubkov, who turns 66 on Saturday, is considerably older than most Russian political leaders.

The country had been expecting Putin to wait until after parliamentary elections in December to indicate his candidate to run for president, perhaps by promoting his favorite to prime minister. Russia’s two first deputy prime ministers _ former Defense Minister Sergei Ivanov and Gazprom board chairman Dmitry Medvedev _ had been considered the leading contenders.

Zubkov had never been mentioned even as a possible dark horse candidate, although he has been part of Putin’s inner circle for many years. He will replace Fradkov, 57, another technocrat, who also was little-known when he became prime minister in March 2004.

Zubkov was praised on state television by a succession of Kremlin loyalists, who described him as an honest, hardworking professional. “He has worked without making noise or raising dust,” Ivanov said.