Labour are now second place just behind the Conservatives according to the latest YouGov poll.
The survey results are the latest in a series of indicators showing a surge of support for Labour in the town.
Liz Savage, Labour's Parliamentary Candidate for Southport, responded:
"This is just further confirmation of what we've been seeing on the doorstep and saying for weeks; the Liberal Democrat vote is collapsing and it is a straight fight between us and the Conservatives. We believe Southport is changing and that it wants change. Labour is closing the gap nationally and locally."
Another poll by Ashcroft has Labour essentially level at just one per cent behind the Lib Dems.
Both polls are highly embarrassing for the Lib-Dems who have been claiming that Labour "can't win" and that "more and more Labour voters" are supporting them.
"I'd like to see the basis for that as none of the polls show it, nor does the recent Liverpool City Region Mayor result breakdown in Southport back it up. It's a shame they have to resort to such negative tactics but it's also quite amusing, let's be honest, they wouldn't do it if they actually thought I couldn't win!"
She also has a clear message for Lib-Dem supporters:
"If you want to stop the brutal Conservative cuts and their hard Brexit stance, we are now the tactical vote here. You need to vote Labour."