Wer soll NRW regieren? Unsere Ministerpräsidentin @HanneloreKraft oder ehem. CDU-Minister, der Kinderbetreuung verschlafen hat? Darum gehts.
— Martin Schulz (@MartinSchulz) May 13, 2017
— Armin Laschet (@ArminLaschet) May 13, 2017
The SPD had been ailing nationwide but saw a surge in support in February when Schulz took over. That support failed however to translate into votes in the last two state elections, when the CDU won comfortably.
Schulz shrugged off the two disappointments.
Sometimes you lose, sometimes you win. I have the impression that Sunday will be a day when we will say 'we win' — Martin Schulz
An election in Germany's biggest state is always significant, but it carries higher stakes this year, being the last regional vote before national polls and having a direct impact on whether the SPD can close the gap nationwide with the CDU.
In the run-up to Sunday's vote, Schulz held more than 30 rallies in the state, where he began his political career in his hometown of Wuerselen.
The party is banking its hopes on incumbent state premier Hannelore Kraft, 55, who secured 39.1 percent in a 2012 vote, while the CDU clinched just over 26 percent.
If Kraft succeeds, then the chances of the SPD's bid to take back the chancellery grow. If she loses, it would mean that the Schulz train has slammed against a wall — Der Spiegel
Schulz is hoping that his push for "social justice" will resonate in North Rhine-Westphalia, which has lagged behind western Germany economically.
SPD blamed for traffic jams
But Merkel has also been pounding the streets in the state of 18 million people, including 4.2 million of migrant origin.
In the town of Haltern am See on Wednesday, she took aim at Schulz's arguments, saying the CDU offers "justice in the sense of jobs, strong budgets, funds for local communities".
"Through intelligent policies and solid finances, and by doubling our investments in research, we have managed to reduce the number of jobless people to half that in 2005 when I became chancellor," she said.
Merkel has also blamed the incumbents for persistent traffic jams that "are longer than from here to the moon".
The populist Alternative for Germany (AfD), which has railed against the migration influx, hopes to win its first seats, which would give it seats in 13 of 16 state parliaments.
TRT World's Ira Spitzer explains why the outcome of the North Rhine-Westphalia state poll could influence what happens at Germany's national election later this year.