Arriving in Brighton I asked a taxi driver for his thoughts on the Liberal Democrats."Not a lot," he replied. "And I don't like the leader, Nigel Farage."This perhaps sums up the problems facing the party: who are the Lib DemsCritics say they are a spent force - running out of road with a lacklustre leadership.But this is not how party members see themselves.They're optimistic, friendly, and courteously committed to the cause.The conference gift shop proudly proclaims that Lib Dem teddy bears have been this year's biggest seller.But soft toys won't save a party - and the reality is, with only 12 MPs, gaining traction is tough.Despite insisting they're still relevant, you can't help wonder if that's true as you wander around the conference stalls.It all feels a bit lifeless. Even Sir Vince admitted the party is very male and very pale. wasn't a great sell. He fluffed his killer line, describing Brexit as an "exotic spresm" - not the "erotic spasm" he had promised.Neither sat comfortably and one of his own MPs, Tim Farron, admitted the bungled joke was an "anti-climax".Lib Dem members left happy, but the party is struggling to convince voters outside conference.A Sky Data poll shows people would far sooner vote for a new anti-Brexit party than vote Lib Dem.There's been a lot of talk about the next leader, too - Sir Vince isn't hanging around after Brexit.The Lib Dem gift shop told me that fridge magnets of Layla Moran, the newbie MP for Oxford West and Abingdon, were "selling fast".I was not told how many magnets were sold, but one party member told me that Ms Moran has had a "good conference".Norman Lamb, a senior Lib Dem MP, acknowledged to me that the party is in the doldrums.He said: "We've been stalling since 2015."He doesn't want the Lib Dems to be single-issue party. But if they're struggling to be heard on Brexit, will anyone listen to their other policy plansAnd there is also a genuine worry that noises about a new leader could end up drowning out the Lib Dems' other political ambitions.