Manmohan Singh, who shed the image of a reticent politician and successfully staked his government on the nuclear deal issue last year, begins a fresh term in office facing challenges on the economic and security front.
76-year-old Singh, a reluctant politician who faced charges of being a "weak" prime minister, emerged unscathed largely on the strength of his image as a man of integrity.
Economy, still reeling under the impact of global downturn, and the problem of security in the aftermath of the worst terrorist attack in Mumbai last year are issues that immediately need attention from the new government.
Singh is widely regarded as one of the cleanest persons in public life, but has never won any election and hence was nominated by his party to the upper house of Parliament.
But he has the distinction of being the only other leader to be prime minister for a second continuous term after a full first term after the first Prime Minister Jawaharlal Nehru.
The former RBI Governor, who had also served as Finance Secretary, had once said that it was not the end of the world if the nuclear deal with the US did not go through, but later risked his government when the Left parties withdrew support.
In the end, the government survived with support from unlikely quarters -- Samajwadi Party, which rescued it.
Singh's handling of the deal and the BJP charge, especially that of its prime ministerial candidate L K Advani, that he was the weakest prime minister during the election campaign brought out the best in him -- qualities a hard-boiled politician would envy.
The civil nuclear deal aimed at securing nuclear fuel to run the country's atomic power plants at full capacity is Singh's key achievement as Prime Minister and ended India's decades of isolation by the international nuclear community.
Singh's greatest contribution, however, is the economic reforms process that he set in motion in the early 1990s.
A D.Phil in economics from Oxford University and author of 'India's Export Trends and Prospects for Self-Sustained Growth' -- an early critique of India's inward-oriented trade policy -- Singh opened the Indian economy, cut taxes and red tape to set the country on the path of high economic growth.
As a result of debt build-up in the early 90s, India was on the verge of default in respect of external payment liabilities, its capital market went into a tailspin, and its sovereign ratings slashed.
It was Singh, who was roped in by P V Narasimha Rao as Finance Minister, who initiated macro-economic reforms that included opening the market to foreign investment and bringing in precious foreign exchange.
There has been no looking back for Singh since then and the high point came in 2004 when Congress president Sonia Gandhi did the 'renunciation act' and nominated the mild-mannered leader as the Prime Minister.
"It was an unbelievable moment-since he was not contesting, he was not trying, he was out of the race...it came out of the blue," Singh's wife Gursharan Kaur said of the day he was named PM.
In fact, Singh has emerged stronger with more room to go ahead with Congress' policies, including on the economic front, especially at a time when the global economy is plunged in a crisis.
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