Row over Israel mars second day of convention as party moves to add back 'God' and 'Jerusalem' language to platform

The Democratic national convention in Charlotte has been plunged into chaos with a row over Israel threatening to overshadow Bill Clinton's speech as the second day of business was mired in a clumsy and embarrassing climbdown.

Barack Obama intervened personally to try and head off a mounting clamour from Jewish donors and pro-Israel groups who objected to the dropping of a line supporting Jerusalem as the capital of Israel from the Democratic policy platform.

A day after the platform was published without the recognition of Jerusalem, the line was reinstated. Pressure had been building over not only the dropping of that statement – which was part of the Democratic party platform in 2008 – but also the removal of any reference to God in the document. Those omissions threatened to alienate both Jewish Democratic supporters and Christian swing voters.

But the reintroduction of the lines was equally controversial; its clumsy handling resulting in a confusing vote and booing on the convention floor.

At the formal opening of the day's business, the convention chairman, Antonio Villaraigosa, proposed a vote to return to the document its past commitment to Jerusalem as the Israeli capital as well as a reference to God.

He called for those in favour of the change to shout 'Aye' and those against 'No'. It was a hard to tell, with the two sounding evenly-divided. Villaraigosa called the vote a total of three times to no certain result but eventually called it for the Ayes.

In fact, the change required a two-thirds vote in favour and it definitely did not sound anywhere close to that. But Villaraigosa pushed it through anyway, determined to try to bring a speedy end to an awkward row. There was loud booing in the hall when he announced the changes had gone through.

Jewish donors, particularly in New York, and pro-Israeli lobby groups are generous supporters not only to Obama but to individual senators and members of the House, who are also facing election in November. The changes were pushed through after Obama contacted party leaders asking for their reinstatement.

Quoting Democrat sources, Jessica Yellin, CNN's chief White House correspondent, reported on Twitter that when Obama was told "God" had been removed from the platform, he responded: "Why on earth was it changed?"

The self-inflicted row came as party leaders were congratulating themselves on the smooth running of the convention's opening day on Tuesday. The Republicans pounced on the original omission as evidence that Obama does not fully support Israel. The subsequent booing on the convention floor was portrayed by right-wing commentators as "Democrats booing God".

Republican challenger Mitt Romney said omitting God "suggests a party that is increasingly out of touch with the mainstream of the American people."

He added: "I think this party is veering further and further away into an extreme wing that Americans don't recognise."

On Jerusalem, Romney's spokeswoman, Andrea Saul, said: "Mitt Romney has consistently stated his belief that Jerusalem is the capital of Israel. President Obama has repeatedly refused to say the same himself. Now is the time for President Obama to state in unequivocal terms whether or not he believes Jerusalem is Israel's capital."

The Anti-Defamation League, a pro-Israel organisation, welcomed the change but questioned why the reference to Jerusalem being the capital had been removed in the first place.

"We welcome the amendment referencing Jerusalem as Israel's capital and we applaud the DNC for listening and for being responsive to the concerns raised by supporters of Israel," said Abraham H Foxman, ADL national director. "But we are still troubled that it was removed, and it should never have happened in the first place. This has been a longstanding policy statement on the DNC platform going back decades."