Julián Castro, the former United States Secretary of Housing and Urban Development and the former mayor of San Antonio, is now running for president. And even though currently he is polling at about 0 to 2 percent in most national polls, he expects that to change as soon voters get to know him. 

"I can’t think of a single time in my life where I haven’t been an underdog. What I am used to doing is working hard. You know,  I am going to walk the walk, in the campaign, in my vision for the future, in working hard and knocking on doors, and getting to those town halls. And I think people will see by the end of it that I can defeat Donald Trump and win this nomination."

Castro, whose grandmother immigrated to the United States from Mexico and then worked here as a maid and a cook, talks to Amy Walter about how he is used to upending people’s expectations. 

Click on the 'Listen' button above to hear this segment. Don't have time to listen right now? Subscribe to our podcast via iTunes, TuneIn, Stitcher, or wherever you get your podcasts to take this segment with you on the go.

Want to comment on this story? Share your thoughts on our Facebook page or Twitter.