Prime Minister David Cameron and his wife Samantha voted at a polling station at his constituency in Oxfordshire while opposition leader Ed Miliband and his wife Justine swept past reporters as they voted in northern England.

Scottish National Party leader Nicola Sturgeon also came out early in Glasgow. She`s not running for a place in the 650-seat Parliament, but her party is expected to win big in Scotland. That may help her become the kingmaker in deciding who runs the government.

Sturgeon has said she wants to make sure "the voice of Scotland is going to be heard more loudly at Westminster than it has ever been heard before," and that SNP supporters should join forces with Labour to lock out the Conservatives.

9:20 a.m. (0820 GMT; 4:20 a.m. EDT)

In the bright early-morning sunshine, voters are gathering to cast ballots at a polling station close to Parliament as police stand guard.

Signs of the unfolding political drama were all around. The squares opposite Parliament were packed with temporary outdoor television studios, while commuters picked up newspapers urging voters to the polls.

"It`s going to be important for Britain for the next five years," said Gerry McQuillan, 61, an arts administrator voting Labour. "We`re coming out of economic austerity but we`ve got to get the right government for the next five years."

Alexis Thomas, 34, a doctor, was mindful of all the predictions of a dead heat and wanted to make her voice heard.

"Because it`s so tight, I think that if I didn`t come out and vote, and didn`t get the result that I wanted, then I`d only have myself to blame," Thomas said — though she wasn`t saying what result that was.

7:50 a.m. (0650 GMT; 2:50 a.m. EDT)

Labour leader Ed Miliband has cast his vote in the U.K. general election.

He voted along with his wife, Justine, in the northern town of Doncaster, on Thursday morning. Miliband has represented the constituency of Doncaster North in Parliament for the past 10 years.

Miliband is the only politician with a realistic chance of taking the post of prime minister away from David Cameron, but neither of their parties is expected to achieve an overall majority in Parliament.

U.K. Independence Leader Nigel Farage also voted early in the southeastern constituency of South Thanet, and then tweeted: "I can`t tell you who I voted for!"

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