This year's race to the White House has seen the most aggressive and expensive election campaigns in history, with video clips taking shape as the best weapons.

Egged on by each other, it was soon established that the initial frontrunners (Barack Obama, Hillary Clinton, John McCain, Mike Huckabee, Ron Paul, John Edwards, Rudy Giuliani and Mitt Romney) would be fighting their causes, and criticising those of their opponents, by summoning up topical, funny, and convincing video clips in record times. Largely distributed online, the clips became an all-encompassing means of persuasion for candidates desperate to get into the White House. If you think John McCain's 320 videos is a lot, it's nothing on Barack Obama's 1820. So it's no wonder that despite over 18 months of bombardment, we're still discovering some gems in the catfight treasure trove. Here's our selection of the best...