Although it isn’t a Liberal Democrat (or Alliance, SDP or Liberal) party election broadcast, this is the one that had the biggest immediate impact on me when I saw it.
It’s a tremendously well put together piece, using music in a powerful and ironic way (at a time when Labour was trying to wrest the reputation of being the patriotic party from the Conservatives) and built around showing the viewer the leading figures of another party celebrating at their own party conference. Showcasing your opponents in this way doesn’t usually work, but they were unusual political times.
The broadcast’s impact will, I suspect, be much less now for people who didn’t live through the politics of that era, though even so it helps explain some of the very strong emotional reactions to political events since the 2010 general election.
When watching, keep an eye out for how Ken Clarke used to be a high profile unpopular Conservative cabinet minister. Repeatedly losing the Conservative Party leadership, but doing so with grace and humility and without in-between times plotting, has helped transform his public character in the intervening years.
(For my other posts on party political broadcasts, including move clips, see my Party Political Broadcasts page.)