>> candidates, please take your positions behind the podiums while we remind you and our audience of the ground rules. each of you will have 90 seconds to answer questions, 60 seconds for responses and rebuttals and 15 seconds for clarifications. timing lights will remind you when time is expiring. >> we also remind our audience here in the auditorium at drake university to be respectful so the candidates can hear the questions and can hear each other. >> just hours ago, the republican field narrowed once again former new jersey governor chris christie ended his bid for the presidency. so, with one fewer candidate in the running, let's start with the decision voters here in iowa are about to face. governor desantis, why should voters who are looking for an alternative to the current front-runner, former president trump, vote for you rather than