Here's a sketch that failed to get into Newsjack. I have to admit, I thought this had a better chance than most of my submissions, so I'd be interested to see where everyone thinks I could improve it.
In retrospect, the only big mistake I can see was not including an introduction to contextualise things a bit (for reference, the sketch is predicated on Vince Cable's recent defence of the coalition governments budget/immigration policies that appear to conflict with the Lib Dem's campaign positions). Alternatively, it may be too short (though it comes out at a minute plus if you read it aloud, which I thought was just long enough for the joke to make its point and get out, so I'm unsure if length is a huge concern)
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VOICEOVER: Have you recently been involved in an accident in Parliament? Found yourself voting for measures you campaigned vigorously against? If so, you might want to consider ...Vince Cable.
VINCE:I know we campaigned against a VAT rise, but frankly, we changed our minds when we got a good look at how much money we'd make.
VOICEOVER:The New Improved Vince Cable will defend any policy position on a no-win, no-fee basis. After all, as a Lib Dem propping up Conservative ideologies, he can't possibly win, and in the long run, he's the one who's going pay.
VINCE:At this point in the recession there simply aren't enough rich people left to tax, which is why we've decided to go after those mooching, lazy poor people.
VOICEOVER:Vince Cable comes with a unique, non-stick surface from which any criticism will simply wipe clean, leaving you - and your party - free to betray any principle you like.
VINCE:I think you'll find that the Liberal Democrats have had a long-standing and open support for an immigration cap, dating as far back as last month when we were all given our own offices.
VOICEOVER:Vince Cable is a well-respected and much-beloved politician that works straight out of the box. Simply place in a cabinet position, wind up and watch him go! Vince Cable! Now available in blue.