Brazil general elections kick off

A man kneels down in a voting booth as he casts his vote during Brazil's general elections at a polling station in Sao Bernardo do Campo, near Sao Paulo October 5, 2014. [Photo/Agencies]

BRASILIA -- Millions of Brazilians on Sunday morning began to cast their votes in the first round of general elections for a new president, state governors and national as well as state legislators.

The poll stations nationwide opened at 8 a.m. local time (1100GMT).

Voting in Brazil is compulsory for those aged 18-70, meaning 142.8 million people are expected at the polls. According to Brazil's Superior Electoral Court, voters between the ages of 45 and 59 predominate in this year's elections.

There are three main candidates, including incumbent President Dilma Rousseff, who is running for re-election.

A combination photo shows Brazil's leading presidential candidates (L-R) Dilma Rousseff of the Workers' Party (PT), Marina Silva of the Brazilian Socialist Party (PSB), and Aecio Neves of the Brazilian Social Democracy Party (PSDB) in recent televised debates in Rio de Janeiro (L and C) and San Paulo (R) in these October 2, 2014 (L and C) and August 27, 2014 file photos. [Photo/Agencies]

According to the electoral law, a presidential or gubernatorial candidate must garner more than 50 percent of the vote to win, otherwise the top two candidates from the first round will face a run-off on Oct. 26.

Some 30,000 troops will be deployed to 250 cities across Brazil to ensure smooth voting and to provide logistical assistance, including transporting ballot boxes and election officials in remote areas, the Defense Ministry said.

A Central Command and Control Center, initially established to guarantee security during the 2014 FIFA World Cup, will be used during the elections, the ministry said.