Labour’s candidate in the Batley and Spen by-election said the poll was about the people of the area and not a referendum on the leadership of party leader Sir Keir Starmer.
Kim Leadbeater was speaking after welcoming Sir Keir to the constituency on Thursday as bookies backed the Tories to take the lead in the forthcoming poll.
Ms Leadbeater told the PA news agency: “I think it’s really important the Labour leader comes to Batley and Spen.
“I’ve chosen to stand as a Labour candidate but I’m under no illusion that the Labour Party has got some work to do.
“But I think it’s really important that he comes, he meets the people of Batley and Spen, listens to what they’ve got to say.”
The July 1 poll is being seen as a crucial test for Sir Keir after Labour’s defeat in Hartlepool last month.
But asked if the election was a referendum on the party leader, Ms Leadbeater said: “No, I absolutely don’t see it as that at all. This is about the people of Batley and Spen.
“And it’s about who’s the best person to represent them in parliament.”
She said: “I am the only person out of the 16 candidates that lives in Batley and Spen. Their problems are my problems. I know about the speeding cars and I know about the potholes, because they’re outside my house.
“So, my narrative is very much about ‘this is who I am, I’ve lived here all my life, I was born here’, and I would work my socks off for this area because I love it.”
On Wednesday, the pair were pictured having dinner at the Healds Hall Hotel in nearby Liversedge.
The by-election was triggered after Tracy Brabin, who won the seat for Labour in 2019 with a 3,525 majority over the Conservatives, was elected as the mayor of West Yorkshire in May.
Ms Leadbeater is the sister of former MP Jo Cox, who was murdered in the constituency in 2016.
A total of 16 candidates will contest the by-election, although the poll is being seen as a straight two-way fight between Labour and the Conservatives.
The Tories are pinning their hopes on Leeds councillor Ryan Stephenson.
Former MP and veteran campaigner George Galloway is running for his Workers Party and the Lib Dems have selected Tom Gordon.
The Yorkshire Party, which came third in the recent West Yorkshire mayoral election, will be represented by local engineer Corey Robinson.
The other candidates are: Paul Bickerdike (Christian Peoples Alliance); Mike Davies (Alliance For Green Socialism); Jayda Fransen (Independent); Therese Hirst (English Democrats); Howling Laud Hope (The Official Monster Raving Loony Party); Susan Laird (Heritage Party); Oliver Purser (Social Democratic Party); Andrew Smith (Rejoin EU); Jack Thomson (Ukip); Jonathan Tilt (Freedom Alliance); Anne Marie Waters (The For Britain Movement).