Hungary's ruling coalition headed by Prime Minister Viktor Orban that includes party Fidesz and the Christian Democratic People's Party (KDNP) received nearly half of the votes in the election held on April 8 and thus got a two-thirds majority in the country's parliament, the final results showed on Sunday.
That gives it a two-thirds majority that allows it to steamroll legislation through parliament without the need for approval from any other party. The political opposition is in disarray, civil society is under attack and the news media is nearly fully under the control of the state.
Orban won a third straight term in power in Sunday elections after his anti-immigration campaign message secured a strong majority for his ruling Fidesz party in parliament, granting him two-thirds of seats based on preliminary results. They also urged all opposition parties to be more cooperative.
The protests, which remained relatively peaceful, were attended by over 10,000 people waving Hungarian and European Union flags, reports said.
Demonstrators have demanded a recount of all the ballots, a new election law and non-partisan, independent media - as well as better cooperation among the political parties.
According to AFP reporters at the scene, around 100,000 people took part in the march.
"Viktor Orban has forgotten where he came from", Ors Lanyi, one of the organisers told the crowd, which responded with loud boos upon hearing the prime minister's name.
The protesters also wanted to rewrite Hungarian election laws and remove Fidesz's influence from state-run media.
Jobbik and the Socialist-led alliance will take up 26 and 20 seats respectively.
In the election campaign Orban projected himself as the defender of Hungary's Christian culture against Muslim migration into Europe, an image which resonated with millions of voters, especially in rural areas.