Updated 7:26 p.m., 5/17/2014
Washington (CNN) - President Barack Obama intends to nominate San Antonio Mayor Julian Castro to be his next secretary of Housing and Urban Development, a government source said Saturday.
The 39-year old, three-term mayor first gained national recognition when he delivered the keynote address at the 2012 Democratic National Convention - the first Hispanic to do so.
[twitter-follow screen_name='politicalticker'][twitter-follow screen_name='JimAcostaCNN'][twitter-follow screen_name='ConorCNN']
First elected in 2009 and re-elected in 2011 and 2013, Castro is the youngest mayor of a major American city. He has been widely considered a rising leader in the Democratic Party and some even say a potential vice presidential candidate in 2016.
The current HUD secretary, Shaun Donovan, has been a member of the Obama administration from the start.
A Democratic official with knowledge of the cabinet selection process tells CNN that a plan is now in place for the President to nominate Castro for HUD secretary and tap Shaun Donovan to head the Office of Management and Budget. That position became open after Syliva Mathews Burwell was tapped to replace Health and Human Services Secretary Kathleen Sebelius.
This Democratic official said the vetting process for Castro is still under way and that a formal announcement could be weeks away.
In response to questions Saturday, the White House said, "We have no personnel announcements at this time."
The intended Cabinet shuffle was first reported in The New York Times.
A graduate of Stanford University and Harvard Law School, Castro began his political career at a young age. At 26, he was the youngest councilman ever elected in San Antonio.
Four years later, he ran for mayor, but lost to retired judge and fellow Democrat Phil Hardberger. Another four years, and Castro was in City Hall at the ripe old age of 34.
Castro was re-elected in 2011 with 82% of the vote and in 2013 with 67%.
He has spoken out in favor of same-sex marriage and of affirmative action, even telling The New York Times that it helped him get into Stanford.
Castro has built a reputation as "a youthful and dynamic leader here in town," Walter Wilson, assistant professor of political science at the University of Texas-San Antonio, told CNN in 2012.
Former San Antonio mayor and HUD secretary Henry Cisneros told CNN in an interview that Castro is a good fit for the job, noting the current mayor's record of expanding pre-K education, revitalizing San Antonio's downtown and shoring up the city's finances.
With an eye on 2016, Cisneros said the mayor could "learn the country" as HUD secretary, arguing, "It's a lot more likely he can get on that ticket from a national office than from a mayor's job."
"He can't stay a mayor forever without getting dinged," Cisneros said, noting the Republican Party’s current dominance in Texas politics.
"He will grow into a national-caliber talent," Cisneros continued, saying Castro has the potential to one day become the nation's first Latino president.
Not everyone is a fan, though.
"He's a tax-and-spend liberal. He does not represent all Hispanics, we're not all the same," George Rodriguez, president of the tea party in San Antonio, said in 2012.
Castro is the grandson of Mexican immigrants. His grandmother came to Texas from Mexico as an orphan at the age of 6. She taught herself to read and write in Spanish, eventually finding work in San Antonio as a maid and a cook.
His twin brother, Joaquin Castro, who introduced him at the DNC in 2012, is representing San Antonio in the House of Representatives.
–CNN's Conor Finnegan, Sarah Aarthun, Ed Lavandera and Mariano Castillo contributed to this report.