India is the most populous democracy in the world. A parliamentary republic with a multi-party system, it has six recognised national parties, including the Indian National Congress and Bhartiya Janata Party (BJP), and more than 40 regional parties. The Congress is considered centre-left or "liberal" in the Indian political culture, and the BJP centre-right or "conservative". For most of the period between 1950—when India first became a republic—and the late 1980s, the Congress held a majority in the parliament. Since then, however, it has increasingly shared the political stage with the BJP, as well as with ever more powerful regional parties which have often forced multi-party coalitions at the centre.
In the first three general elections in the Republic of India, in 1951, 1957 and 1962, the Congress, led by Jawaharlal Nehru, won easy victories. In 1964, after Nehru's death,Lal Bahadur Shastri briefly became prime minister, and was succeeded after his own unexpected death, in 1966, by Indira Gandhi, who went on to lead the Congress to election victories in 1967 and 1971. Following public discontent with the state of emergency declared by Indira Gandhi in 1975, the Congress was voted out of power in 1977, and a new party, the Janata Party, which had opposed the emergency, voted in. Its government, however, proved short lived, lasting just over three years. Back in power in 1980, the Congress saw a change in leadership in 1984, when prime minister Indira Gandhi was assassinated and succeeded by her son Rajiv Gandhi, who won an easy victory in the general elections later that year. The Congress was voted out again in 1989, when a National Front coalition, led by the newly formed Janata Dal, in alliance with the Left Front, won the elections; that government too proved short lived, lasting just under two years. Elections were held again in 1991 in which no party won an absolute majority, but the Congress, as the largest single party, was able to form a minority government, led by P.V. Narasimha Rao, and to complete a five-year term.
The two years after the general election of 1996 were years of political turmoil, with several short-lived alliances sharing power at the centre. The BJP formed a government briefly in 1996, followed by one of the United Front coalition, but without the support of either the BJP or the Congress. In 1998, the BJP was able to form a successful coalition, the National Democratic Alliance (NDA), which, under the leadership of Atal Bihari Vajpayee, became the first non-Congress government to complete a full five-year term. In the 2004 Indian general elections, again no party won an absolute majority, but the Congress emerged as the largest single party, forming a successful coalition, the United Progressive Alliance (UPA), with the support of left-leaning parties and MPs opposed to the BJP. The UPA coalition was returned to power in the 2009 general election, the proportion of left-leaning parties within the coalition now significantly reduced. That year, Manmohan Singh became the first prime minister since Jawaharlal Nehru in 1957 and 1962 to be re-elected to a second five-year term.