With the Liberal Democrat spring conference in Birmingham this weekend, Nick Clegg is giving his last conference speech before the general election. Who knows, there may even be two general elections before he gets to give his autumn conference speech…

So what does Nick need to achieve with his Sunday speech?

Conference speeches have two audiences: the external and the internal. For the external one, the job is in the main fairly straightforward: give a speech that has at least one eye-catching section which means it gets more than a nano second of passing media coverage.

The party’s overall messages for the general election are nicely taking shape, as reflected in the Why Vote Liberal Democrat book. Debates over mansion tax and tuition fees have been concluded. The weakness on how to present our approach to improving public services looks much less of a problem when given a good lick of fairness paint.

The only serious hiccup in recent weeks on messaging is that Labour too have pinned their election message on fairness with an election slogan featuring the word ‘fair’. The challenge for Nick Clegg (and the rest of the party) will be to spell out our approach in a way that is distinct from Labour’s.

However, as we get closer to polling day the ‘anti-squeeze’ message becomes increasingly important. The election is not just a choice between Labour and Conservatives; indeed, only a minority of constituencies are Labour-Tory contests. For the majority of the country, it’s a different choice. But mixing the pragmatic and principled reasons for people to ignore the national squeeze messages from the other parties – putting it all into an interesting and persuasive soundbite is not always easy.

The one other issue, as I highlighted in my book review, is that the party’s policy approach is distinctly light on how to deal with the changes being brought about to society, the economy and government by the internet. There is one issue on which the party has got many news headlines for its policy stance – but they have overwhelmingly been negative for the headlines have been about *that* amendment to the Digital Economy Bill. That is an issue that gets noticed many voters and sets an impression of whether a party understands the modern world, especially for the young graduates for whom the Iraq war was such a powerful message last time, but also crucially for many activists or would be activists.

Firing up this internal audience, even without the Digital Economy Bill problem, would be a key part of Nick’s speech. Moreover, at times in previous speeches Nick has talked about the importance of building up a wider liberal movements and tapping into the liberal heart of the country. However, that has only rarely been transformed into more direct efforts to build up a larger campaigning presence on liberal issues as opposed to the very focused one on target seats. We’ve not seen, for example, any equivalent of the Democrat 50 States strategy, aiming to get a record number of Liberal Democrat local election candidates this year.

So those are the four challenges: can Nick grab the public’s attention, how does he present the anti-squeeze message, can he fire up activists and will he give an impetus to campaigning not just in key seats but in a way that builds a broader liberal movement? And with all the talk about the internet and the general election, who knows – he may even slip a web address into the speech in the way that has become common for so many politicians elsewhere.