Google speech team demos their speech recognition technologies, videos from YouTube's Politicians channels are automatically transcribed from speech to text and indexed. You can add an iGoogle Google Elections Video Search gadget that is restricted to a small number of political videos from YouTube. Since the gadget is actually an iframe, you can also go to the original page.
Using the gadget you can search not only the titles and descriptions of the videos, but also their spoken content. Additionally, since speech recognition tells us exactly when words are spoken in the video, you can jump right to the most relevant parts of the videos you find.