This is a poster by Gui Borchert from the “Artists for Obama” series. The image of Obama and the cropped “yes we can” in the background are created solely with type using words from Obama's speeches. As a portrait, this conveys not only Obama's appearance but the ideas and ideals for which he stands. It is a complex and beautifully organized piece.
The font is either House Industry’s Chalet Comprime or Hoefler & Frere-Jones' Knockout. The latter is the closest match and also the most likely candidate as the Obama campaign has diligently used Gotham, another H&F font, throughout its campaign. No last-minute, "We need more signs for this rally! Let's just use Arial!" for the Obama campaign. They have been incredibly consistent and organized regarding their graphic design. The campaign also has inspired some quality artistic production such as this poster. Most importantly, I love the content of their message.