Leaders of the Spanish and Portuguese Jews' Congregation are taking legal advice after a challenge to the result of last night's election of Rabbi David Bassous as their next spiritual head.

In a ballot of members yesterday, London-born Rabbi Bassous gained exactly the minimum two-thirds majority to secure the position, with 268 votes for him and 134 against.

But opponents of his appointment have now asked to inspect two doubtful or spoilt ballot papers.

A senior figure in the community commented; "This is the same as Al Gore v George Bush" – alluding to the 2000 American presidential election which hinged on the legality of a few voting papers.

The result was declared after four recounts following the ballot at the community's flagship synagogue, Lauderdale Road in London. In an email circulated in the early hours of this morning, S and P chief administrator Howard Miller told members; "As the votes cast for the appointment therefore constitute at least two thirds of the valid votes cast, Rabbi Bassous's appointment is approved.

"There has been a request from representatives of those against the appointment to view the spoilt or doubtful ballot papers. Advice is being sought in relation to this request and is expected to be received on Friday."

Rabbi Bassous, who serves a Sephardi congregation in New Jersey, spoke to all four Spanish and Portuguese synagogues during a visit to London last week. He had been unanimously recommended by the congregation's executive and board of elders. Ahead of Thursday's night vote, the executive of the S and P had emailed members alerting them to a "vicious and unpleasant campaign that is being conducted in your name against the potential appointment of Rabbi Bassous".

If the vote is upheld, he will succeed Rabbi Abraham Levy, who has been spiritual head of Britain's oldest Jewish community since 1980.