Liveblogging CNN’s GOP debate in Arizona with Bloomberg Businessweek, Jeff Greenfield, Yahoo News & ABC News

The 2012 presidential race hinges on what happens in Michigan on Tuesday, so of course all of the Republican candidates are in Arizona. It's the 20th debate of the campaign, and the last--presumably--before Super Tuesday on March 6.

During the debate, read and contribute to our liveblog, which will feature real-time discussion and analysis from Yahoo News and ABC News journalists, as well as tweets from Yahoo News reporters on the ground in Arizona. (You can follow the liveblog below, or go to this page, which has also been optimized for tablet and mobile devices.)

The liveblog will feature Rick Klein, the senior Washington editor for ABC News' "World News with Diane Sawyer"; Olivier Knox, the White House correspondent for Yahoo News; Walter Shapiro, who writes the "Character Sketch" column for Yahoo News; Chris Suellentrop, the deputy editor for blogs at Yahoo News, including The Ticket; and Z. Byron Wolf, the political editor of ABCNews.com and a deputy political director for ABC News.

Also participating will be Jeff Greenfield, Joshua Green, and Weston Kosova.

Jeff Greenfield, a veteran political correspondent and the host of PBS' "Need to Know," is the author, most recently, of Then Everything Changed, which will be published in paperback next month.

Joshua Green is a national correspondent for Bloomberg Businessweek. Follow him on Twitter at @JoshuaGreen.

Weston Kosova is the Washington editor for Bloomberg Businessweek.

More popular Yahoo! News stories:

• Romney retools his message as his lead shrinks in Arizona

• Who would bomb Iran? Santorum, Romney, Gingrich & Paul on the nuclear threat: Character Sketch

• Obama, Romney release dueling tax plans

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