With 100 votes cast in Brazil so far, 73 congressmen have opted in favour of impeaching President Dilma Rousseff over her alleged financial cover-up.
A total of 27 either voted against the motion or abstained.
A minimum of 342 votes from the lower house's 513 MPs is required for proceedings to pass to the Senate.
Report by ITV News' Senior International Correspondent John Irvine
MPs in Brazil's lower chamber have begun voting on whether to impeach President Dilma Rousseff over accusations of corruption.
President Rousseff has been accused of manipulating the country's finances to hide a worsening economic crisis - but she denies any wrongdoing.
Brazilians are divided over the issue and if she is impeached the country could be plunged into chaos.
Pro and anti impeachment supporters have taken to the streets of Brazil as they headed towards the Palace of Congress to make their voices heard as the country's lower house decide on whether or not to push for the impeachment of President Dilma Rousseff.
A fence called the 'wall of shame' has been put up ahead of a vote to decide whether to impeach Brazil's President Dilma Rousseff amid claims she manipulated government accounts to allegedly favour her re-election in 2014.
Located outside the Palace of Congress in Brasilia the fence is reportedly intended to separate rival supporters who are expected to gather outside as the lower house decide whether or not Ms Rousseff should be impeached.
If two-thirds of lower house members vote in favour of impeachment tonight, the case will be sent to the senate for trial.
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