Presidential Debate Preview with the Globe's Scot Lehigh

As you may have heard by now, tonight's debate is being billed as do-or-die for President Obama. Gov. Mitt Romney's task is somewhat simpler — he has to build on his strong leadoff performance from a couple weeks ago. Rest assured, supporters and political operatives will be glued to their screens and Twitter feeds tonight, seizing on zingers and parsing facts as fast as the candidates can fling them.

Between keeping the candidates in check and getting the audience involved as well, moderator Candy Crowley will have her hands full tonight.

Scot Lehigh joins Emily Rooney to talk through Tuesday's debate.

GUEST:

MORE:

You can watch the debate tonight on WGBH channel 2 starting at 9 P.M. You can also listen on 89.7 FM, or stream it on our website.