WASHINGTON -- The road to confirmation will likely be long and difficult for the first Latino picked to serve in President Barack Obama’s Cabinet during his second term.

The Obama administration on Monday tapped Thomas Perez, the assistant attorney general for civil rights at the Justice Department, to lead the Department of Labor.

Seen as an unabashed advocate for immigrant rights and other liberal causes, Perez is expected to play a leading role in Obama’s efforts to overhaul immigration laws and raise the minimum wage.

Opponents are planning to block his nomination by painting him as a poster boy for big government who pushes an intrusive agenda, and they already have a bill of particulars prepared: that he blocked laws in Texas and South Carolina that require photo IDs at the polls and that a recent critical report by the Justice Department inspector general found that his division suffered from “deep ideological polarization.”

“This is an unfortunate and needlessly divisive nomination,” said Sen. Jeff Sessions, R-Ala., a senior member of the Senate Judiciary committee, which overseas the Justice Department. “The top priority of the secretary of labor should be to create jobs and higher wages for American workers. But Mr. Perez has aggressively sought ways to allow the hiring of more illegal workers.”

Speaking from the East Room of the White House, Obama described the Harvard University-trained lawyer born to immigrant parents from the Dominican Republic as a dedicated public servant whose upbringing and success “reminds us of this country’s promise.”

“If you’re willing to work hard, it doesn’t matter who you are, where you come from, what your last name is, you can make it if you try,” the president said. “And Tom has made protecting that promise, for everybody, the cause of his life.”

Before becoming the nation’s civil rights enforcer, Perez served as Maryland’s labor secretary for two years. He also served in the Health and Human Services Department’s civil rights office under President Bill Clinton and was an aide to the late Sen. Edward Kennedy, D-Mass.

If he’s confirmed, Perez will replace another Latino, outgoing Secretary Hilda Solis, who resigned after Obama’s first term. Latino groups concerned about a lack of diversity in the Cabinet praised Perez’s selection. Labor groups see him as an ally.

Cathy Ruckelshaus, legal co-director at the National Employment Law Project who worked with Perez in Maryland, said he knew how to balance the needs of unions and employers.

“He’s pretty unique,” Ruckelshaus said. “He’s balanced and fair, but also has a lot of passion for laws he’s called upon to enforce.”

His confirmation is no sure thing, foreshadowing another possibly nasty fight for an administration that’s had to battle – and even retreat from the field – for some of its recent nominees. Obama withdrew U.N. Ambassador Susan Rice’s name for secretary of state after she became embroiled in a controversy surrounding the fatal Libyan consulate attack last September. Former Republican Sen. Chuck Hagel endured a bruising Senate hearing before being confirmed as secretary of defense.

“Detractors are likely to claim he’s an aggressive advocate of race-conscious civil rights policies and that he’s also not sufficiently protective of the rights of American citizen workers,” said Rogers Smith, a political science professor at the University of Pennsylvania.