Accusations of anti-Semitism have led to widespread criticism of Labour in recent months.
Some supporters have warned it could lose out at future elections unless the relationship is repaired.
At this week's party conference, Labour leader Jeremy Corbyn told delegates he wanted the party and the Jewish community to "work together and draw a line" under the anti-Semitism row.
Indeed, relations have been strained for some time, with an inquiry into anti-Semitism in the party launched in 2016.
Last month Labour adopted the International Holocaust Remembrance Alliance's definition of anti-Semitism, although critics said the addition of a "caveat" undermined the international definition.
Now, a study of results at the 2017 general election suggests some damage may already have been done before the row intensified this summer.
It appears Labour may have underperformed in the constituencies with the most Jewish people.