Polls closed at 10pm last night. Picture: Steve Robards

Mrs Cooper prevailed in yesterday’s Marine Ward by-election in West Worthing, which had been triggered by the resignation of Conservative Joan Bradley in May.

The result follows an impressive showing by Labour in June’s general election, where Mrs Cooper stood against current MP Peter Bottomley.

Although unsuccessful Mrs Cooper increased her party’s vote share by more than 10,000.

Mrs Cooper is the first Labour representative on Worthing Borough Council for more than 40 years, according to the party.