"It's not enough to be ahead in the polls, we have to come first on voting day too", he said, recalling his party's loss in a 2002 election, at the end of his first term as prime minister, despite having been considered the favourites beforehand.
The strongest opposition party is former far-right Jobbik, which has recast its image as a more moderate nationalist force.
'Today will decide whether Hungary becomes an emigrant country or not - and I wouldn't like Hungary to be an emigrant country, ' Mr Vona said. Opposition parties are keen to make sure Mr Orban's bloc does not sweep to a super-majority in which the autocratic leader could easily push through constitutional changes.
In last elections of 2014, Orban's coalition Fidesz-KDNP won 133 seats, securing two thirds of the parliament, also known as a super majority.
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Marine Corps jet crashed at the country's global airport and a Marine Corps helicopter sustained "minor damage" Tuesday. On March 15 an HH-60 Pave Hawk transport helicopter crashed in western Iraq, killing seven airmen.
Rivals say that leaves open the possibility of an upset and are urging voters to turn out in record numbers.
A man in the capital, Budapest, said he hopes the ruling party will win. In Hungary's complex electoral system, voters cast two ballots - one for a candidate in their voting district and another for a party list.
In all, 199 seats in parliament are up for grabs.
Orban's main challengers are Gergely Karacsony, the candidate of the Socialist and Dialogue parties, and Gabor Vona from the nationalist Jobbik party.
The fierce anti-immigrant campaign has gone down well with around two million core voters of Fidesz.
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It was not immediate possible to confirm the details of the deal and there was no comment from the Army of Islam. More than 1,600 of Eastern Ghouta's 400,000 have died since the offensive began in February.
For rebellions such as refusal to meet EU requirements on accepting mass migration, accusations of violations of university freedom, freedom of assembly and association, social rights, and alleged "everyday corruption", the European Union could stop money going to Hungary, or even insist Hungary repays funds already given.
After casting his vote in a wealthy district of Budapest, he said he would stand up for Hungary's interests and said Hungary was a loyal member of global organizations.
Vona's Jobbik party started out as xenophobic group well known for its anti-Semitic views.
"Safety is first", said Julia Scharle, 27, holding her child outside the polling station where Orban cast his vote. He claims the European Union, the U.N., Hungarian-American financier George Soros and the civic groups he sponsors are all conspiring to force Hungary to take in thousands of mainly Muslim migrants to weaken its independence and its Christian identity and culture.
Orban is expected to continue his economic policies, with income tax cuts and incentives to boost growth, analysts have said.
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