Key details of the 2012 US presidential debates

President Barack Obama and Republican challenger Mitt Romney are preparing to square off Wednesday night in the first of three prime-time debates. Tens of millions of Americans are expected to tune in.

President Barack Obama and Republican challenger Mitt Romney are preparing to square off Wednesday night in the first of three prime-time debates. Tens of millions of Americans are expected to tune in.

Here are the key facts and figures about the face-to-face showdowns that could shape the presidential campaign down the stretch to election day on November 6.

All debates are coordinated by the non-partisan Commission on Presidential Debates. Each debate starts at 9:00 pm eastern time (0100 GMT) and runs for 90 minutes.

First presidential debate:
Wednesday, October 3 at University of Denver, in Denver, Colorado.

Moderator: Jim Lehrer, executive editor for PBS NewsHour.

Format: Six 15-minute time segments each focusing on one issue. Moderator asks an opening question, and candidates have two minutes to respond. Remainder of time used for discussion.

Topics: The US economy health care the role of government governing.

First and only vice presidential debate:
Vice President Joe Biden v. Romney's running mate Paul Ryan.

Thursday, October 11 at Centre College, in Danville, Kentucky.

Moderator: Martha Raddatz, senior foreign affairs correspondent, ABC News.

Format: Nine 10-minute segments. Moderator asks an opening question, and candidates have two minutes to respond. Remainder of time used for discussion.

Topics: Domestic and foreign issues.

Second presidential debate:
Tuesday, October 16 at Hofstra University, in Hempstead, New York.

Moderator: Candy Crowley, chief political correspondent, CNN.

Format: Town meeting, in which citizens -- undecided voters selected by polling group Gallup -- ask questions. Candidates each have two minutes to respond.

Topics: Domestic and foreign issues.

Third and final presidential debate:
Monday, October 22 at Lynn University, in Boca Raton, Florida.

Moderator: Bob Schieffer, chief Washington correspondent, CBS News.

Format: Identical to the first debate.

Topics: Foreign policy.