LONDON — Concluding one of the most passionate election campaigns in years, Britain went to the polls on Thursday after a frantic race to the finish among politicians clamoring to persuade voters that they offer the best prospect of economic change and social renewal.
But the election, after 13 years of rule by Prime Minister Gordon Brown’s Labour Party, was clouded by the possibility that it could end in stalemate with none of the three leading contenders securing the 326 seats needed for an absolute majority in the 650-seat Parliament and thus the uncontested right to choose the next prime minister.
Some 44 million people — roughly three quarters of the population — were registered to vote for their choices among 4,149 candidates at around 50,000 polling stations. Counting begins immediately after the polls close at 10 p.m. local time.
As early voters headed for polling stations, most opinion surveys and political analysts said the Conservative opposition leader, David Cameron, 43, seemed to hold a comfortable lead over his rivals — Mr. Brown and Nick Clegg, leader of the smaller opposition Liberal Democrats.