President Trump told Politico in an interview on Tuesday night that he's "totally" willing to shut down the government if he doesn't get $5 billion approved for a wall along the U.S.-Mexico border, calling the issue "a total winner" politically.

Why it matters: The fight over border wall funding has been a long time coming, but Trump has backed down before after threatening a shutdown over the summer and before the midterm elections. Senate Democratic leaders have said they would approve $1.6 billion for border security, but GOP sources told Politico they think Democrats "will want to strike a deal so they start 2019 with a fresh spending slate." The fight comes as the administration has shifted its focus to the caravans of Central American migrants seeking asylum at the border.