Londoner go to the polls Thursday to pick a new mayor, as a hotly contested race between a former mayor and the man who ousted him comes to an end.

The election between incumbent Boris Johnson and Labour’s Ken Livingstone, who led the city from 2000 to 2008, is widely seen as a preliminary referendum on Conservative Prime Minister David Cameron, who has lost much popular support as Britons deal with a recession and austerity measures meant to temper budget overruns.

But Cameron may be more worried about a win by party rival Johnson, which could catapult him over the prime minister’s head as the party’s No. 1 if the party fares poorly, as it is expected to do, in local elections across England.

Cameron isn’t the only one fretting over Thursday’s vote. A win by leftist Livingstone, known as “Red Ken” for his views, would put the city’s Jewish community once again under a mayor who has repeatedly bashed Israel and Jews while embracing political Islam.

Speaking in March at the North London Central Mosque, which was formerly the base of the radical Muslim preacher and terrorist recruiter Abu Hamza, Livingstone vowed to “educate the mass of Londoners” in Islam. “That will help to cement our city as a beacon that demonstrates the meaning of the words of the Prophet… I want to spend the next four years making sure that every non-Muslim in London knows and understands [the prophet’s] words and message,” he said.

Livingstone has drawn no small amount of ire from non-Labour Londoners for his outspoken statements and left-wing views, but he also managed to alienate the Jewish flank of his own political base over his campaign, reportedly calling them “rich” Jews who “won’t vote for me anyway.”

In the end, the Jewish Labour faction reluctantly decided to endorse Livingstone, saying he may “irritate, upset and annoy,” but would still be an improvement over Johnson, the Jewish Chronicle reported last week.

Johnson has consistently led in the polls, pushing Livingstone to abandon the identity politics approach that served him in the past and cast the vote as a referendum between the Conservative and Labour parties.

“Some of us may find one of us funnier than the other, but in the end there are two parties, two sets of policies, two sets of values. That is what matters. A vote for the Conservative candidate in such a vital election is, in the end, a vote for what the Tories are doing to our country and our city,” Livingstone said, according to the Guardian.

Johnson is still expected to win a second term Thursday, according to polls. The results will likely be announced Friday.

Miriam Shaviv contributed to this report