The firing gun has been sounded in the race to replace Tom Watson as deputy Labour Party leader after Dawn Butler announced her intention to stand.
Speaking to Bloomberg TV, Ms Butler said: “I’ve thought very carefully about who should replace Tom and after giving it some thought, I will be throwing my hat in the ring.”
Mr Watson dramatically quit as deputy to Jeremy Corbyn on Wednesday evening, the first official day of the election campaign.
In a letter, he also confirmed he would not be contesting the West Bromwich East constituency, a seat he has held for 18 years.
With clamour inside the party growing for its inaugural female leader, shadow equalities secretary Ms Butler is the first out of the blocks in the bid to ensure Mr Watson is replaced by a woman.
The opposition frontbencher is often seen sitting next to Mr Corbyn during Prime Minister’s Questions.
On the left of the party, she sparked controversy at last year’s Labour conference when she praised the former Militant-led Liverpool council in the 1980s for setting budgets in excess of the limits imposed by Westminster.
Ms Butler told delegates it was “better to break the law than break the poor”.
The 50-year-old Londoner is looking to position herself as pro-Corbyn and a voice for minority groups at the top of the party in the upcoming deputy leadership contest.
“I think I’ve got a track record of countering, holding people to account around race, equality and justice,” she said.
“I’ve got a track record of being very supportive to our leader Jeremy Corbyn and ensuring the Labour Party is on the front foot.
“There are structural barriers that hold people back. I want to as deputy leader change all of that, change the way the country is currently developing, change the way we’re seeing hate overcome hope, change the script on all of that.”
Ms Long-Bailey has been mentioned publicly as a potential future leader and the high-profile figure revealed a slick video and personal logo on social media this week, a move interpreted internally as an early leadership bid, according to the New Statesman magazine.