It takes a bit for Labor not to preference the Greens but on Friday it was announced that in the Melbourne seat of Macnamara, where Jewish MP Josh Burns is embattled, the ALP will run an open ticket.

Macnamara, which includes the suburbs of Balaclava, Albert Park and South Melbourne, has the second largest Jewish constituency - 10% of voters - of any electorate. Only Wentworth in Sydney has more.

Burns has held the seat since 2019. At the last election he had a primary vote of 31.77%, with the Greens second on 29.65%, just ahead of the Liberals on 29%. After preferences were distributed, this turned into a substantial two-party win for him over the Liberals.

The political dynamics have changed since then. There is anger in the Jewish community about the Albanese government's attitude to Israel and criticism that it hasn't done enough to combat antisemitism. The expectation is that Burns' primary vote will go down and the Liberal vote will go up.

ABC election analyst Antony Green says the seat "will be a battle for the order of exclusion" - it will all depend on who comes in third on primary votes.

If the Liberals or the Greens come third, Burns will be elected. If Burns is third on primaries, he is eliminated and the Greens are favorite, even with an open ticket. But the leakage of preferences from an open ticket would give an opportunity to the Liberals, Green says.

Green points out that given how close the three parties were on primaries last election, a very small shift in votes could change the order of the top three.

Burns has benefitted from the Friday draw for order on the ballot paper. He is in the top spot, giving him the so-called "donkey vote", with the Greens third, ahead of the Liberals.

Burns warned an election forum this week, sponsored by the Australian Jewish News and various Jewish groups, "If we do not win enough number one votes, then the Greens will obviously come into second place. That is the biggest concern that I've got."

He dismissed the prospects of the Liberals being able to win the seat. "The only people who can win this seat from me are the Greens."

He told the audience, "If the Greens form into the top two, then think about the people who make up this electorate - the young progressive people from Elwood, from St Kilda, from Windsor, from South Melbourne, from South Bank.

"We are a proud and large Jewish community, but we're only 10% of the electorate of Macnamara.

"The preferences, regardless of what the Labor Party says, are not going to the Liberal Party from those young people."

Burns faced some heckling from a small number of people in the audience - they were told to be quiet by other audience members.

The forum was attended by Liberal candidate Benson Saulo, who recounted his Indigenous heritage, and strongly condemned the scenes at the pro-Palestinian rally outside the Sydney Opera House in the wake of the October 7 2023 Hamas attacks in Israel.

The Greens candidate was not invited onto the panel but was in the audience.