The shadow foreign secretary has until midnight to get the backing of three more grassroots Labour groups or she will be out of the leadership race.
The MP for Islington South and Finsbury had 30 nominations this morning out of the 33 she needs to get on the ballot.
There were 17 constituency Labour parties still to declare out of a total 647, although they do not have to nominate a candidate.
Her rivals have already secured their places on the ballot after winning the backing of major unions.
Front-runner Sir Keir Starmer has endorsements from 370 constituency parties, while Leftwinger Rebecca Long-Bailey is on 159 and backbencher Lisa Nandy is on 71.
The nominations are seen as a good indication of the views of local members. Last night Sir Keir praised Ms Thornberry for speaking out against anti-Semitism during shadow cabinet meetings.
At a hustings hosted by the Jewish Labour Movement, he said: “We spoke up in shadow cabinet. We had a lot of rows. And I want to pay tribute to Emily. She spoke up loud and clear, sometimes the row went on for the whole of the meeting.”
It comes after Ms Thornberry, below, accused shadow business secretary Ms Long-Bailey of inaction over the issue.
All four Labour leadership candidates apologised to Jewish members over the party’s handling of the crisis during the debate at the Liberal Jewish Synagogue.
Mike Katz, national chairman of the movement, said they would be holding the next leader to account over their promises to rid the party of anti-Jewish racism.
Ms Long-Bailey said she had spoken out about the issue but could have “done more”. She was due to give a speech in Salford today arguing that the party must “forge a path to power”.