According to the polling, the Free Democrats and Alternative für Deutschland (AfD) have picked up support and will qualify for seats in the new Parliament, where they had none before because they fell below the 5% qualification threshold in the popular vote.
Of those, 31.7 million are women and 29.8 million are men. Merkel's bloc took 41.5 percent nationwide last time, its best performance since 1990, the year Germany was reunified under CDU Chancellor Helmut Kohl.
Voter apathy has been evident in recent German elections. The 2013 election produced a 631-seat parliament.
AfD supporter Guenther Poppe, a 69-year-old pensioner, said he refused to be stigmatised for his vote.
Why do they have two votes?
One of the party's two main candidates, Alice Weidel, denounced the comments as anti-democratic. The second is for a party list.
Even for close observers of Germany's humdrum election campaign, identifying the policy differences between the big parties can be hard.
The option of another grand coalition between Ms Merkel's conservative alliance and the SPD remains possible if the party sustains its position in the polls above 20 per cent of the votes.
Younger SPD voters are unimpressed with their party's performance since entering the coalition. Could the same be said nowadays about the German chancellor herself?
An absolute majority of the Bundestag's members is required to elect a chancellor.
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Who are the key parties? And Mrs Merkel hasn't had to work particularly hard to see off the diminishing challenge of social democrat Martin Schulz.
As we walk along the lakeside here, among gulls and swans, Rolf Kronhagel explains why he shifted his allegiance to AfD. Conservatives want lower taxes while Greens want to tax the super rich. Greens have a more liberal migrant policy which could pit them against the CSU, and they oppose plans to increase defense spending.
Merkel has come under criticism for her open door refugee policy. But the party is ideologically close enough to the centre-right CDU to allow for cooperation in parliament. But it has generally remained a junior partner and an occasional king maker.
It has a focus on greater social justice and promises labour and welfare reforms. What appeared to be missteps - such as a private email exchange in which party leader Alice Weidel reportedly attacked Germany's democratic system and called the ruling political class "pigs"- did little to halt the AfD's momentum.
Therefore, the struggle to secure power doesn't end on election day, but continues until the parties manage to form a coalition.
This may complicate the creation of a coalition and will leave Merkel in need of more compromises with others to construct a government. On the other hand, the party and its supporters make large use of negative campaigning against AfD's competitors, in the first place, unsurprisingly, Angela Merkel.
A minority government would be a first and stability-craving Germans would not like it but may prefer it to new elections.
Depending on the shape of the coalition, the main issues at stake are the integration of the more than 1 million migrants who have arrived in Germany in the last two years, and investment in Europe's biggest economy as well as Merkel's leading role in talks on reform of the European Union and relations with Russian Federation and Turkey. It contributes money to the European Union budget more than any other member.
The UK has already chose to divorce the European Union. After the shock of Brexit and the victory of Donald Trump in the USA, elections in the Netherlands and France would either push the European project forward or cause new internal crises with unpredictable consequences. In a year when there was a chance of right-wing populist victories in the Netherlands and a real risk of France (Europe's second-largest economy) tearing up the European Union treaty and blowing up the Eurozone, Germany has threatened no such upsets.
"If these three points are not clarified, we will not be able to advance on the rest", Macron said. The S.P.D.'s leader, Martin Schulz, enjoyed about ten minutes this spring when he seemed charming and new, and moved higher in the polls.