The Liberal Democrats and the UK Independence Party (UKIP) have chosen their candidates for the Hanover and Elm Grove by-election.
UKIP has chosen Patricia Mountain, from Hove, while the Lib Dems have selected Lev Eakins, 35.
He moved to Brighton and Hove in the past year to run a business with his brother.
Until four months ago he worked as a housing income management officer at Brighton and Hove City Council.
Mr Eakins was born and grew up in Sussex before moving to Manchester to study for a degree in politics. He now lives in the Brunswick area of Hove.
Five years ago he was elected to Manchester City Council, winning a seat from Labour, and he served a four-year term.
He was known as Martin Eakins during his time in Manchester where he also stood at the 2010 general election in Wythenshawe and Sale East, coming third.
He said: “Brighton is one of the most socially liberal cities in the country with a proud tradition of non-conformity amid a vibrant and diverse community.
“I’m offering the good citizens of Hanover and Elm Grove an authentic Liberal voice to represent their community.
“I’m delighted my party have selected me to contest this seat and honoured the citizens of Hanover and Elm Grove have nominated me.
“If elected, I would ensure that local residents have a dedicated councillor who keeps in touch all year round and listens carefully to the needs of the community.”
The vacancy arose when Green councillor Matt Follett resigned from the council saying that he was moving away from the area.
Diversity is overrated.