Secretary of Housing and Urban Development Julian Castro , left, and Labor Secretary Tom Perez. (AFP/Getty Images, AP)

On Wednesday, Labor Secretary Thomas Perez stood with Vice President Biden in Ohio to formally unveil changes to overtime work rules long sought by the nation’s labor unions.

In coming days, Housing and Urban Development Secretary Julián Castro plans to announce changes to how the government sells “underwater” mortgages — another key concern of liberal groups.

Long touted as potential Democratic running mates with appeal to Hispanic voters, Castro and Perez are taking steps to boost their progressive credentials and prove they also have professional qualifications for the job as the formal vetting process nears.

Administration officials and close associates insist the policy moves have been in the works for years and have nothing to do with jockeying for the vice presidency. But every move by Castro and Perez is now scrutinized through a political prism.

Multiple people who have spoken with both men say they want to be Hillary Clinton’s vice president, understand the potential historic nature of their selection and are taking steps now to fit into the moment.

Secretary of Housing and Urban Development Julián Castro. (Brendan Smialowski/AFP/Getty Images)

“They are not just one-trick ponies,” said Henry Muñoz, finance chairman for the Democratic National Committee and a co-founder of the Latino Victory Project. “They bring serious weight and diverse perspective. They’re symbolic and substantial.”

Javier Palomarez, president and chief executive of the U.S. Hispanic Chamber of Commerce, so eagerly wants a Latino vice president that his group has already taken the unusual step of endorsing Castro for the job.

“I think the next president will need to stand with and by the fastest-growing demographic in this country,” he said, adding later that “in an electoral cycle where xenophobia and anti-Hispanic rhetoric is not only included but is dominating the rhetoric, choosing Julián as VP would send an amazing signal of hope and reconciliation.”

Other activists warn that Democrats can’t afford to assume that Hispanic voters will turn out in droves just because presumed Republican presidential nominee Donald Trump has made comments that are offensive to many Latinos.

“Having a Latino vice president I think would be a key incentive for Latino voters and communities,” said Hector Sanchez, head of the National Hispanic Leadership Agenda. “But it’s not enough to just have somebody with a particular racial background. It’s important that that person shows the commitment they have for policy priorities that are good for the nation.”

The changes both secretaries announced this week, which have been in the works for years, are being closely watched by progressive groups.

Edwin Cooley, left, talks to Labor Secretary Thomas Perez, far right, about an apprenticeship program on May 13 in East Providence, R.I. (Matt O'Brien/AP)

Starting Dec. 1, full-time salaried employees can earn overtime pay if they make up to $47,476 annually, more than doubling the current threshold. The Labor Department, making changes for the first time in a decade, estimates that about 4.2 million workers will be helped.

In a trip that could serve almost as a test-drive for the part, Perez accompanied Biden to Columbus to unveil the new rules. At the flagship store of Jeni’s Splendid Ice Creams, Perez delivered a speech that was part biography and part politics, focusing on liberal values around the middle class.

“I love my job,” Perez said, explaining that before becoming labor secretary he had run the Justice Department’s civil rights division. “My job is to be a guardian of the crown jewels.”

Biden also brought with him another politician mentioned as a potential Clinton running mate, Sen. Sherrod Brown, the union-friendly Democrat from the critical swing state of Ohio.

But only Perez earned a shout-out in a statement from Clinton, who said, “I applaud President Obama and Secretary of Labor Perez for these final overtime rules, which will lift up workers nationwide and help get incomes rising again for working families.”

At HUD, Castro is putting the final touches on changes to how the Distressed Asset Stabilization Program sells off bad mortgages. More than 105,000 mortgages have been sold off since the program launched in 2012. But critics argue that the buyers are predominantly private-equity firms and hedge funds instead of nonprofit groups that are more likely to be concerned about the financial needs of lower-income homeowners.

Castro has been working to revamp the program since 2014, aides said, and has met with advocates and groups seeking the changes, including Sen. Elizabeth Warren (D-Mass.), who is often mentioned as vice-presidential material.

But he has also earned the ire of an umbrella group of liberal organizations that launched DontSellOurHomestoWallStreet.org and a petition drive to force Castro to move faster.

“He has presided over a policy that enables Wall Street bankers to destabilize and extract wealth from our communities, drive up the cost of housing and exacerbate and profit from foreclosures, displacement and gentrification, at a large scale,” said Matt Nelson, managing director of Presente.org, a Los Angeles-based Latino advocacy group.

In response to criticism about the pace of reforms, HUD spokesman Cameron French said that the department has tweaked the program “nearly a dozen times and is evaluating further changes.”

Such criticism from the left has angered some Latino activists. Maria Teresa Kumar, who leads Voto Latino, a voter mobilization group, faulted Presente and other groups with trying to “take down Latino leadership.”

“By trying to delegitimize the few voices we have in the mainstream, I find it not only toxic, but it makes the work we do so much harder,” she said, adding that such criticism could damage the chances of someone already facing tough scrutiny because of ethnicity.

Robert Shrum, a veteran Democratic strategist who helped lead the vice-presidential selection process for John F. Kerry’s 2004 presidential campaign, said this week’s announcements probably will have little bearing on Castro’s or Perez’s fate. The Clinton campaign is already deeply familiar with their backgrounds, he said.

Absent the vice presidency, Castro and Perez supporters believe that they are at least owed promotions in a future Clinton Cabinet. Perez, a veteran of the Justice Department, could be a choice for attorney general, while Castro could serve as secretary of commerce or education, leading a department he worked with as a big-city Texas mayor.

Nelson said his group and others will keep up the pressure — especially if either man is tapped for a promotion.

“With the increase in Latino leadership, part of our core mission is to build Latino political power, and with that is also holding people accountable,” he said. “This is how democracy functions.”

Paul Kane in Columbus contributed to this report.

Corrections: An earlier version of this article misstated Javier Palomarez’s title at the U.S. Hispanic Chamber of Commerce and had an incorrect launch year for the Distressed Asset Stabilization Program.