India has begun a crucial round of state elections that may determine whether an early general election will be called, BBC reported.
Voters are casting their ballots in 39 of 90 constituencies in the first stage of polling in the central Indian state of Chattisgarh.
Voting in six mostly central and western states will take place over six weeks amid signs of economic slowdown.
A general election must be held by May but could be called earlier.
Correspondents say that key issues include rising prices and security following a spate of bomb attacks blamed mostly on Islamist militants.
Apart from Chattisgarh, the states that will go to the polls are Madhya Pradesh, Delhi, Mizoram in the north-east and the western desert state of Rajasthan.
For security reasons disputed Jammu and Kashmir will vote district by district in seven phases over nearly as many weeks.
If the governing Congress party does well, it may want to build on the results and call an early poll in February.
However, a poor performance might prompt the government to delay the vote until May, the end of its five-year parliamentary term.
Whichever party - Congress or the main opposition BJP - does better may find it easier to secure alliances with regional parties before the general election - of the utmost importance when building a post-election governing coalition.
The BJP faces a tough challenge from Congress in Madhya Pradesh, Chattisgarh and Rajasthan because incumbent administrations in Indian states often do badly in elections.
Observers will also be closely watching the outcome of the vote in Indian-administered Kashmir, which during the summer was the scene of large anti-India protests.
The global economic meltdown has had serious repercussions for the Indian economy and growth has been hit in the past year.
Rising inflation and increasing prices of essentials, including foodstuffs, will be a major issue in the elections.
The deteriorating security situation will also be a consideration with voters.
Many Indian cities, including Bangalore, Jaipur, Ahmedabad and the capital, Delhi, have been hit by bomb blasts recently, with large losses of life.
The BJP has been campaigning for a tougher anti-terror law in response to the bombings.
Counting of votes will take place on 8 December, apart from in Indian-administered Kashmir where votes will be tallied on 28 December.