The SPD had surged from 16 points behind the CDU/CSU in mid-January to a 33-32 lead in mid-February after nominating Martin Schulz as chancellor candidate. The SPD held even with the CDU/CSU at 33-33 until early April before falling behind.
Merkel's conservatives won three regional elections in the last three months while the initial euphoria surrounding Schulz, a former European Parliament president, wore off.
Despite the widening lead, Merkel's CDU/CSU is far short of a majority and might have a difficult time finding a junior coalition partner. Their preferred partner, the Free Democrats (FDP) were steady at 7 percentage points in the Emnid poll.
The pro-environment Greens, who could form a center-left coalition with the SPD or a center-right alliance with the CDU/CSU, were up 1 point to 8 percentage points. The far-left Left party were steady at 9.
The far-right Alternative for Germany (AfD), ostracized by the other parties and without any coalition partner options, was steady at 8 percentage points.
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