Sir Ed Davey smashes the “Blue Wall” in by-election celebration

The transcript discusses the Liberal Democrats' campaign as underdogs, addressing voter concerns in Chester. It highlights the role of Sarah Green and the party's commitment to environmental issues. The metaphor of an 'orange force' challenging a 'blue wall' is used to illustrate their political impact.

What is the main goal of the Liberal Democrats as stated in the text?

What metaphor is used to describe the political landscape in the text?