Ian Leslie compares Clegg and Obama:
[Clegg] has characteristics that play well on TV: energy and likeability, a certain classlessness, and an ability to speak human. But - and here's the key - he's also quite bland. He doesn't have a Scottish accent or ginger hair or a military bearing. There's nothing memorable about him. So while he's spent the last three years putting together a reasonably credible policy platform, the public have ignored him (I swear there would have been quite a few voters watching last week's debate surprised to discover that Cameron and Clegg were two different people). It's as if he's been lying in camouflage, invisible to the voters, only to spring an ambush four weeks before election day.
Different political systems reward different strategies. If you want to be an agent of change in America, it's better to stand out from the beginning, as Obama did by virtue of his skin colour, his name, and his charisma - then prove you've got substance over the long haul of a primary campaign. But if you want to do the same thing in Britain, be bland, and blend into the background - then seize your moment at the last minute.