The Labour (PvdA) party has now overtaken the more hard-left Socialists (SP), themselves rising stars just two weeks ago, thanks to the performance of charismatic leader Diederik Samsom, 41, in televised debates.
Both parties are still trailing the Liberal PVV but in the Netherlands it is never just one party that forms a government and tough negotiations will begin after election day to hammer out a coalition.
"Samsom is very relaxed during televised debates, notably because he knows his topics extremely well," Bert van den Braak, political analyst at Leiden University, told AFP.
"On the other hand, (Socialist leader) Emile Roemer has found it difficult, he's been caught out on some subjects during the debates," he added.
Andre Krouwel, political scientist at Amsterdam University, said: "Samsom managed to give the impression of a potential prime minister, someone able to lead a coalition government."
Both the PvdA and SP are opposed to further austerity measures to get Europe out of its sovereign debt crisis and favour the stimulus measures promoted by France's Socialist President Francois Hollande.
But the PvdA, less radical than the Maoist-rooted SP, are perceived as being much more likely to compromise and become part of government, Van den Braak said.
Latest polls say that the VVD will win around 34 seats, compared to 31 in the last election in 2010.
The SP, which won 15 seats in 2010 and enjoyed a spectacular surge in popularity just two weeks ago, has ever since been losing potential voters to PvdA, which won 30 seats in 2010.
Latest polls show the PvdA pulling ahead with 29 to 32 seats while the Socialists would win only 22 to 26. And analysts say the Socialist slide and Labour's rise will both continue.
While not as extreme as far-right leader Geert Wilders, who wants to leave the EU and the eurozone, the Socialists are opposed to transferring further responsibility to Brussels and to the European Stability Mechanism (ESM).
It was disagreement over an austerity budget aimed at bringing the Dutch deficit below the eurozone's 3 percent limit that collapsed VVD Prime Minister Mark Rutte's government in April.
The PvdA wants more European integration but, wary of public opinion that is hostile to Europe, is ill at ease to admit it.
"To resolve this euro crisis, we must share more responsibilities, beyond what we feel comfortable with," Samsom said during a televised debate last month.
Analyst Van den Braak said: "There's a strong anti-European, anti-Brussels sentiment in the Netherlands, a feeling that Brussels is not democratic, that the Netherlands has less and less influence on its own affairs."
"I think that the PvdA is in the same situation as a lot of other parties," he added.
"They know that Brussels will have to have a bigger role, that Brussels is a good thing, but they don't dare say it too loud for fear of scaring voters."
Nicolas Delaunay / AFP / Expatica
Where is the best place to be an expat? If you think it's a European country, you're incorrect. In fact, according to HSBC's global Expat Explorer survey, only one European country made the top five.
Join Expatica's online community to reach out for expats just like you!
Share your experience of doing business in the Netherlands, and your business mission, with thousands of other expats.
A guide to telephone, internet and television along with utility services water, electricity and gas in the Netherlands.
Lost in the Dutch immigration system? Look no further than this guide compiled for our Survival Guide 2012.
Expatica offers a whistle-stop tour of life in the modern Netherlands.
The challenges and benefits of the maternity system in the Netherlands and how it differs to other countries.