SAN ANTONIO (CBSDFW.COM) – Joined by his wife Erica and their two children, Democrat Julian Castro told supporters after serving three terms as San Antonio Mayor and HUD Secretary for President Obama, he’s ready for a bigger stage.  

“I am a candidate for President of the United States,” said Castro, 44. “I’m running for President because it’s time for new leadership.  Because it’s time for new energy.  And it’s time for a new commitment to make sure that the opportunities I’ve had are available for every American.”

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With the campaign slogan, “One Nation, One Destiny”, Castro criticized President Trump and his call to build a wall or barrier along the southern border. 

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“The President called it a national security crisis,” said Castro. “Well, there is a crisis of leadership. Donald Trump has failed to uphold the values of our great nation. We say no to building a wall and say yes to building community. We say no to scapegoating immigrants, and yes to Dreamers, yes to keeping families together, and yes to finally passing comprehensive immigration reform. Yes, we must have border security, but there is a smart and humane way to do it.”

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Castro also supports medicare for all, raising the minimum wage, and says climate change is the biggest threat to prosperity.

Standing in the west-side San Antonio neighborhood where he grew up, he also talked about his legacy as mayor.

He convinced voters to raise the sales tax to expand full-day Pre-K for thousands of four year old children in the city.

“Here in San Antonio, I made PreK4SA happen,” said Castro. “As President, we’ll make Pre-K 4 the USA happen.”

Castro is the first Texas Democrat to enter the race.

Former El Paso Congressman Beto O’Rourke, who lost a close Senate race, is also considering running for President in 2020.

Cal Jillson, an SMU political science professor,  said Castro has work to do.

“I think that O’Rourke has some early energy and Castro is going to have to gain some momentum,” said Jillson.

Jillson said there could be as many as two dozen Democrats running in the primary.

They include Hawaii Congresswoman Tulsi Gabbard who announced Friday she will run for President, Massachusetts Senator Elizabeth Warren who has announced an exploratory committee, former Vice President and Senator Joe Biden, Vermont Senator and former Presidential candidate Bernie Sanders, California Senator Kamala Harris, Minnesota Senator Amy Klobuchar, New York Senator Kirsten Gillibrand, New Jersey Senator Cory Booker, Ohio Senator Sherrod Brown, and former New York City Mayor and billionaire businessman Michael Bloomberg.

When asked what Castro has to do to separate himself from the rest of the field, Jillson said, “I think people who look at Castro will see a legitimate candidate. They’ll see an attractive personality with some real accomplishments.  What they’ll wonder, does he have the grit, does he have the backbone, does he have the rhetorical skills to standup to Donald Trump in a debate setting or throughout a campaign?  I think the Democrats want to find someone who can confront Donald Trump, either on his own ground, or by showing a very different, more controlled, more thoughtful public persona.”

For now, Jillson believes Biden and O’Rourke are the early favorites.

“The contrast there is exactly what Democrats will be deciding on: Do you want a 70 year old former Vice-President, long-time Senator who knows world leaders and knows the issues confront the country or do you want a new personality, do you want the dynamism, do you want the energy, do you want the fresh look of someone like Beto O’Rourke?”

At the end of his announcement, Castro told supporters, “Let’s go work.  Vanamos!”

He’s set to travel to Puerto Rico where he will address the Latino Victory Fund Political Summit Monday.

Castro will then fly to New Hampshire where he will take part in “Politics and Eggs” at Saint Anselm College.

During a conference call with reporters before Castro’s announcement, Texas GOP Chairman James Dickey said, “The Democratic field continues to move to the left and are candidates least likely to work with Republicans.”

In a statement, Texas Democratic Party Chair Gilberto Hinojosa said, “Texas Democrat Julian Castro reflects a new generation of Democratic leadership, represents the rising American electorate, and offers a historic candidacy.  We are excited that so many Democrats are considering candidacies to be our nation’s President.”