Iowa caucus: What the outcome will mean for Democrats

With no clear frontrunner ahead of the Iowa caucuses, Monday's vote will change the race for Democrats. CBS News political contributors Jamal Simmons, who worked for President Bill Clinton and advised President Barack Obama's 2008 campaign, and Robby Mook, who ran Hillary Clinton's 2016 presidential campaign, join "CBS This Morning" to discuss what the outcome of the vote could mean for the Democrats.