Former Labour MP Jenny Chapman, who lost her Darlington seat to the Conservatives at the General Election, said it was "patronising" to think traditional Labour voters wanted the "next leader to have ovaries, or a northern accent".
The former shadow Brexit minister is backing Sir Keir Starmer, the shadow Brexit secretary and man behind Labour's shift to supporting a second referendum, for leader.
"I spent the last couple of months talking to folks on the doorstep in Darlington and getting very clear messages back, as you can imagine," she said.
"What people are saying is that they want a leader that they feel could be the prime minister.
"It was about, 'do I trust this person with my mortgage, with the future, with my children, with my pension?'
"And I think that Keir has the qualities that they're looking for."
She told BBC Radio 4's Today programme: "Nobody on doorsteps of Darlington said the next leader has to have ovaries or a northern accent, and I think that's such a patronising attitude to think that presenting someone who speaks the northern accent means you're going to win support in the North."