Barack Obama debating Bobby Rush in 2000. Notes from Mitt Romney's lecture to Mormon students at Harvard Business School on self-improvement. PBS Frontline is releasing a trove of documents, photos and videos from the presidential candidates' past for their "Artifacts of Character" series.

In addition to releasing four new "artifacts" each week, PBS is hosting a discussion with journalists who have written on the moments that defined the candidates, including Washington Post reporter Jason Horowitz and associate editor David Maraniss.

Here's the debate from Obama's primary campaign against Rep. Rush, a rare political defeat for the president (and worth watching in advance of next week's debate between Obama and Romney). 

See all the artifacts from this week and the ones released last week here and jump in the conversation with Maraniss, Horowitz and other journalists about what they learned from exploring the PBS archives here