The Republican presidential contenders took their latest debate  to Las Vegas on Tuesday night, where they discussed immigration, health care, and the economy. The debate was tense at times as Rick Perry tried to regain his momentum, and Mitt Romney defended his Massachusetts health plan. Candidates also briefly weighed in on the Occupy Wall Street movement.  Did Herman Cain prove to be a viable opponent to Mitt Romney? And did Rick Perry help his chances, or further sink his campaign? Todd Zwillich, Washington correspondent for The Takeaway, and Leslie Sanchez, author of "Los Republicanos," recap Tuesday night's event.