More than a dozen candidates are vying for the Democratic nomination to earn the right to face incumbent President Donald Trump.
Michael Bloomberg has filed to run in Alabama’s Democratic primary, but he hasn't decided whether he will actually run.
Former Massachusetts Gov. Deval Patrick, shown in a 2017 file photo, has announced his entry into the Democratic primary on Nov. 14.
Former Congressman and South Carolina Governor Mark Sanford suspended his campaign in November in his bid for the Republican nomination. (Source: WCSC/Gray News)
Beto O'Rourke became the latest Democrat to announce an end to presidential run in 2020. The former congressman vied unsuccessfully for the Senate in 2018 and gained name recognition during that marquee race. (AP Photo/Eric Gay, File)
Out: Rep. Tim Ryan, D-Ohio, shown in Storm Lake, Iowa, Saturday, March 30, announced April 4 that he is running for president in 2020. He dropped out in October 2019. (AP Photo/Nati Harnik
Former Democratic Vice President Joe Biden officially announce his candidacy on Thursday, with a YouTube video denouncing President Trump's response to white nationalist violence in Charlottesville, VA in 2017 and saying
en. Bernie Sanders, the Vermont independent, is one of the strong Democratic hopefuls. But he had a health scare and had two stents recently implanted, raising questions about his health and age.. (AP Photo/Chris O'Meara, File)
Sen. Elizabeth Warren announced on New Year's Eve she is launching an exploratory committee, the first step in launching a presidential campaign. Sheis a favorite with left-leaning Democrats for her efforts to protect consumers. Warren was criticized earlier in 2018 for releasing her DNA findings to prove Native American ancestry after President Donald Trump challenged her. (Michael Swensen/The Boston Globe via AP, Pool)
Sen. Cory Booker, D-NJ, is one of the Democratic contenders polling below 10 percent. (AP Photo/ Cheryl Senter)
Joe Walsh, a former Illinois congressman, says he'll challenge President Donald Trump for the Republican nomination in 2020. The tea party favorite argues that Trump is unfit for the White House. (AP Photo/Carolyn Kaster, File)
Former Congressman Joe Sestak, center, shown in a 2016 photo with his wife Susan Sestak, left, and daughter Alex Sestak, has become the latest Democrat to enter the presidential race. The retired Navy admiral who calls himself
Montana Gov. Steve Bullock announced his candidacy via YouTube video. The Democratic governor of a red state is planning on taking on money in politics.
Sen. Michael Bennet, D-CO, announced May 2 he is running for president. His profile was raised after he lambasted Sen. Ted Cruz, R-TX, on the floor of the Senate for his "crocodile tears" over the government shutdown on Jan. 24, 2019. (AP Photo/J. Scott Applewhite)
South Bend, IN, Mayor Pete Buttigieg has thrown his hat in the ring officially as a Democratic contender. His profile has grown exponentially in a short time. (AP Photo/Nam Y. Huh)
Bill Weld is challenging President Trump in the 2020 Republican primary. He is the first Republican to do so, saying the country is “in grave peril” and he “cannot sit quietly on the sidelines any longer,” according to the Boston Herald. He is a former Massachusetts governor and is shown in 2016 when he was running as the Libertarian vice presidential candidate as part of Gary Johnson's ticket. (AP Photo/Juan Labreche/file)
Miramar, FL, Mayor Wayne Messam, shown fifth from left at the 2015 opening of a FBI headquarters,said he's running for president and considers his status as a relative unknown as something that works in his favor. (AP Photo/Wilfredo Lee, Pool)
Democratic Sen. Amy Klobuchar of Minnesota announced her candidacy in a snowstorm. She has drawn support from voters in urban, suburban and rural areas, including in dozens of counties Trump won in 2016. Klobuchar will be in Iowa on Saturday, Dec. 1, 2018. (Source: CNN)
Marianne Williamson, a spiritual author, announced on Jan. 28 that she was running for president.
Yes, she's running. Sen. Kamala Harris, D-CA, announced on the Martin Luther King Jr. holiday that she is running for president, and by some accounts, she's already a front-runner. The Senate Judiciary Committee member joined by from left, Sen. Mazie Hirono, D-HI, and Sen. Richard Blumenthal, D-CT, in this Sept. 28, 2018, photo. (AP Photo/Carolyn Kaster)
Rep. Tulsi Gabbard, D-HI. announced she is running for president. An early supporter of Bernie Sanders' candidacy in 2016, she also supports
Julian Castro, a Housing and Urban Development secretary under President Barack Obama, announced his campaign bid in San Antonio, TX. He is also a former mayor of San Antonio and has been considered a rising star in the Democratic Party since delivering a speech in 2012 at the Democratic National Convention. His twin brother, Joaquin Castro, is a Democratic congressman. (AP Photo/Charlie Neibergall File)
Rep. John Delaney, D-MD, speaks to fairgoers during a visit to the Iowa State Fair, Aug. 10, in Des Moines, IA. He announced his intention to run for president earlier this year and is seen as a long shot to win the nomination. (AP Photo/Charlie Neibergall)
Billionaire Tom Steyer has entered the 2020 presidential race, he announced July 9.
Rep. Seth Moulton, D-Mass., ended his bid for the Democratic nomination Aug. 23. He is known for his recent attempt to block Nancy Pelosi from regaining the speakership in the House of Representatives. (AP Photo/Carolyn Kaster)
New York Mayor Bill deBlasio, shown in a 2017 file photo at the California state Capitol, ended his campaign on Sept. 20 as he struggled to gain attention in the crowded Democratic field. (AP Photo/Rich Pedroncelli/file)

SAN ANTONIO (AP) — Former Obama housing chief Julian Castro is now in the 2020 Democratic race for president, and he could end up being the only Latino in what’s expected to be a crowded field of White House contenders.

The 44-year-old Castro kicked off his campaign Saturday in San Antonio, his hometown. He announced his official entry in the race during an event in a Spanish-style plaza less than 200 miles from the U.S.-Mexico border.

President Donald Trump visited Texas this past week to press his case for a border wall. He's demanding billions from Congress to build a barrier that's the sticking point in what's now the longest government shutdown in U.S. history.

Castro was San Antonio mayor for five years and was housing secretary during President Barack Obama’s second term.

Copyright 2019 Associated Press. All rights reserved.