Jess Phillips today pleads with fellow Labour MPs, activists and supporters to stick with the party and not follow Tom Watson out of politics, arguing that it is “the greatest vehicle for positive, hopeful change” that this country has ever created.

After a week in which both the Tories and Labour have suffered campaign setbacks and controversies ahead of the 12 December general election, Phillips writes in the Observer that quitting Labour now would mean abandoning the best and only vehicle for fighting division and injustice at a crucial moment.

Although she has been critical of Jeremy Corbyn and admits she is “maddened” by some senior party figures, the rallying call by someone seen by many as a possible future leader will be welcomed by the leadership.

Politics of hatred won’t be beaten if I walk away from Labour Read more

“The rise of the politics of hate and division will not be beaten if I walk away,” Phillips writes. “When I talk with my boys in years to come I want to be able to say that I stayed on board to stop the hatred, division and regression. This brilliant vehicle for social change may need some repairs as it heads down the road, so I will get out my jump leads and, with others, I’ll try to keep it going.”

After a week in which Tory cabinet minister Jacob Rees-Mogg was forced to apologise for suggesting that victims of the Grenfell Tower fire lacked “common sense” for not defying fire service advice and fleeing the building, and the Welsh secretary Alun Cairns had to resign over a former aide’s links to a rape case, both parties are trying to steady themselves for the five-week run into polling day.

Today’s Opinium poll for the Observer shows Labour has cut the Tories’ lead from 16 points a week ago to 12. The Tories are down one point, on 41%, while Labour is up 3, on 29%. The Lib Dems are down 1, on 15%, and the Brexit party is down 3, on 6%.

Both main parties were involved in further internal controversies last night. Corbyn said he was looking into reports that Dan Carden, a member of his shadow cabinet, sang “Hey Jews” to the Beatles song Hey Jude on a private bus to London from the Cheltenham races in March last year. Carden denied the allegations, saying: “I have been categorical in my denial about allegations relating to a coach trip some 20 months ago.

“This was a coach full of journalists and MPs. If anyone genuinely believed any antisemitic behaviour had taken place, they would’ve had a moral responsibility to report it immediately.” Corbyn said it was an “awful story” and “totally unacceptable” if true.

Labour’s national executive was under pressure from 27 of the party’s female politicians to block the candidacy of Kate Osborne, who, at the 2017 election, posted an image of Theresa May with a gun to her head. Osborne, who is standing in Jarrow, has apologised but Labour figures, including Phillips, Yvette Cooper and Lucy Powell, have urged the NEC to bar her. “When women in public life are facing unacceptable levels of intimidation, sharing this image not only indicates an extreme lack of judgment, but further feeds into the cycle of abuse that we are all experiencing,” they wrote to the party’s general secretary.

Meanwhile, the Tory peer Sayeeda Warsi was embroiled in a bitter spat with a colleague, the health secretary, Matt Hancock. She accused him of “whitesplaining” Islamophobia to her after he suggested there were others who took “a more balanced approach” to the issue than she did.

Antony Calvert announced yesterday that he would not try to contest the Wakefield seat for the Tories after a number of his inflammatory social media posts were revealed.

Facebook Twitter Pinterest Jeremy Corbyn with the Labour MP Caroline Flint inspect flood damage during a visit to Conisborough, South Yorkshire. Photograph: Danny Lawson/PA

• This article was amended on 12 November 2019 because an earlier version said Antony Calvert announced he would not try to “retain” the Wakefield seat for the Tories. That seat is held by Labour.