Caroline Lucas is the Green Party's best hope at the 2015 general election. Lucas, the party's former leader, became the first ever Green MP in 2010 when she was elected in the Brighton Pavilion constituency.

General election 2015: Brighton Pavilion constituency candidates

Chris Bowers - Liberal Democrats

Nigel Carter - Ukip

Caroline Lucas - Green

Clarence Mitchell - Conservative

Howard Pilott - Socialist

Purna Sen - Labour

Nick Yeomans - Independent

Now she is battling to keep the seat but faces a number of challenges – not least from her own local party, which has had a controversial few years in control of the council.

As part of a series on marginal constituencies in the UK, IBTimes UK travelled to Brighton Pavilion to take a look at what is going on in the close-fought election campaign.