NEW DELHI - When a mild-mannered, Oxford-educated economist unexpectedly became India's prime minister four years ago, many feared he would be a puppet of his party's top leader. After all, he had never won a direct election and was seen as too academic for the intrigue and intensity of Indian politics.

But Manmohan Singh's apolitical background and squeaky-clean image were also his biggest assets. His name did not figure in any coterie or corruption scandals. As finance minister in the 1990s, he had fearlessly heralded India's economic reforms by quoting Victor Hugo: "No power on Earth can stop an idea whose time has come."

Now, as prime minister, the Sikh is fighting the biggest political battle of his career as he tries to implement another radical initiative, one that he hopes will transform India in the 21st century: the historic nuclear energy agreement with the United States.

The agreement would give India access to nuclear fuel and technology, even though it has refused to sign the Nuclear Nonproliferation Treaty. For months, however, the deal appeared to be near collapse because of opposition from Singh's allies and his adversaries. Critics said it would erode India's sovereignty, tying the country to U.S. strategic interests and taking away its right to conduct nuclear tests.

When Singh, 75, dug in his heels and staked his reputation on the deal, the old charges about his lack of political acumen resurfaced. Colleagues and political observers wondered whether it was worth fighting for an issue that risked pushing the government toward an early election. Singh's term ends in May, and his Congress party was wary of going to polls at a time when inflation rates are at a 13-year high.

Some political analysts said the prime minister was trying to leave his mark on history. The newsmagazine Outlook ran two consecutive cover stories about Singh. "Personal ego or national interest?" one headline asked. Another said simply: "The Great Gamble."

An opinion poll in Outlook found that 73 percent of those living in India's big cities said inflation was a more pressing issue than the nuclear deal.

Confidence vote set

Last week, a coalition of communist parties withdrew its support from the government to protest the deal. The withdrawal precipitated a political crisis, and the government now faces a confidence vote in Parliament on Tuesday. Singh's party is scrambling to cobble together support from smaller, regional parties and independent lawmakers.

Meanwhile, the communist leaders are holding nationwide rallies calling Singh a stooge of the United States.

"Our prime minister is more interested in honoring his commitment to George Bush instead of attending to people's problems," Prakash Karat, leader of the Communist Party of India (Marxist), said at a public gathering in New Delhi last week.

But Singh has argued at every turn that the deal is crucial to achieving energy security for the power-starved, emerging economy of more than a billion people. He said the deal protects India's strategic military program and does not take away India's right to conduct a nuclear test in the future.

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