Poll: Merkel's challenger Schulz boosts German center-left

Candidate of the German Social Democrats, SPD, for the upcoming elections and former President of the European Parliament Martin Schulz speaks during a news conference at the party's headquarters in Berlin, Germany, Monday, Jan. 30, 2017. SPD is backing Schulz to lead their campaign to unseat Chancellor Angela Merkel in the elections. (Bernd von Jutrczenka/dpa via AP) (The Associated Press)

German Chancellor Angela Merkel jokes prior to the weekly cabinet meeting in the chancellery in Berlin, Germany, Wednesday, Feb. 1, 2017. (AP Photo/Ferdinand Ostrop) (The Associated Press)

A new poll indicates that Germany's center-left Social Democrats have gotten a boost by nominating former European Parliament President Martin Schulz to challenge Chancellor Angela Merkel in the country's September election.

It was the third survey in recent days to reach a similar conclusion.

Wednesday's Forsa poll for Stern magazine and RTL television put the Social Democrats' support at 26 percent, up five points from a week earlier. Still, they remained well behind Merkel's conservative Union bloc, which slipped two points to 35 percent.

Schulz became Merkel's challenger when Vice Chancellor Sigmar Gabriel unexpectedly said he wouldn't run. Schulz has a reputation for plain speaking but is untested in national politics.

The poll of 2,502 people, conducted Jan. 23-27, gave a margin of error of plus or minus 2.5 points.