Hillary Clinton is thought to be choosing between two mild-mannered, white swing-staters for vice president on the one hand, and a scrappy Latino progressive on the other, according to NBC News.
The stark choice, between either Virginia Sen. Tim Kaine and Agriculture Secretary Tom Vilsack, or Labor Secretary Tom Perez, could tip the presumptive Democratic nominee's hand about what kind of general election campaign she wants to run.
Does she want to focus on driving up turnout among the Democratic Party's most loyal supporters? Or does she want to reach out to voters the middle, expecting Donald Trump will both turn off moderates and do Democrats' job for them in firing up the base?
Perez, a career civil rights prosecutor whose wife is a lawyer at a legal clinic for the homeless, seems to have found himself as both the last person of color and the last real liberal standing in a field of possible VP picks that had included people like Elizabeth Warren and Housing Secretary Julian Castro.
Allies see Perez as Clinton's best option to excite Democrats, especially Latinos, and heal the divide with Bernie Sanders supporters. Meanwhile, his selection would not jeopardize a Senate seat, as Kaine's pick might.
But some Democrats have concerns about Perez's level of experience, especially on foreign policy, and view Kaine or Vilsack as safer choices.
Either way, both Hillary and Bill Clinton are said to be extremely impressed with Perez, along with several of her top aides, and many Democrats say he'd be a shoo-in for attorney general consideration if he doesn't get the vice presidential spot.
Tony Coelho, the former congressman and chairman of Al Gore's presidential campaign, has become one of Perez's biggest boosters in the semi-public campaign for the vice presidency. "For the last two years, I've been advocating every place I could. Individuals, groups, I've introduced him as the next vice president of the United States," he said.
"The Republicans don't like him. Well that's fine, they're not going vote for her anyway," Coelho added. "I think the issue is who does he turns on?"
Take almost any hot-button issue progressives care about today, and Perez likely has some accomplishment to point to on it. While leading the Department of Justice's Civil Rights Division and later the Labor Department, Perez has been a utility player in the Obama administration on some of the most sensitive issues.
Race and policing? He investigated the Trayvon Martin shooting and launched a record number of probes into police practices. Immigration? He sued Maricopa County Sheriff Joe Arpaio in Arizona and challenged the state's tough immigration law in court. Wall Street reform? He extracted settlements from big banks and implemented new rules on financial advisors for retirement accounts.
Economic inequality? He helped extend overtime pay to 4.2 million workers and was an early advocate of the $15 minimum wage. LGBT Rights? He helped create the Matthew Shepard Hate Crimes Prevention Act and oversaw its first prosecutions. Voting rights? He challenged voter ID laws in Texas and South Carolina. The list goes on.
"His portfolio of civil and human rights and labor issues literally touches every aspect of American society," said Wade Henderson, the president of the Leadership Conference on Civil and Human Rights, who has known Perez since the future-secretary was a staff attorney for Ted Kennedy.
A child of Dominican immigrants who helped pay for one of his two Ivy League degrees by working as a garbage collector, Perez can easily navigate different strata of government and the Democratic Party.
"Tom can speak to many audiences in our very diverse nation in a way few can," said Henderson. "That makes him a unique leader for the 21st Century."
He's charismatic and energetic. When Perez speaks publicly, he tends to grabs the microphone and walk around the stage with it, rarely using a teleprompter but also rarely going off message.
And while Perez can't take full responsibility for some accomplishments, since they were stated before he got to the Labor Department, he was still vital, said Gene Sperling a former White House economic official.
"What he did really well is, he came in and owned them and championed them and used his great personally to get it done," said Sperling.
Clinton calls herself a progressive who likes to get things done, and Perez could help her maximize the impact of executive authority, his allies say. Republicans will likely control at least one chamber of Congress indefinitely, so Clinton has vowed to leverage the federal bureaucracy.
And at time of heightened tensions around race and policing, Perez could be an ideal emissary.
Meanwhile, since organized labor trusts him, the White House has used Perez as go-between on the Trans Pacific Partnership, the massive trade pact that Perez and President Obama support. Perez could play a similar role for Clinton.
"The overwhelming majority of Sanders' grassroots supporters will never have heard of him, but he would be seen as very credible to insider reformers and the word would go forth," said former Rep. Brad Miller, who was a top ally of financial reformers in Congress.
Joseph Geevarghese, who runs Good Jobs Nation, a union-backed campaign to raise labor standards for federal workers, said Perez's selection would help build "a bridge between the economic populists and the economic royalists in the Democratic Party."
"If Secretary Perez was selected to be the vice presidential candidate it would signal that economic inequality and workers rights would be at the top of Secretary Clinton's economic agenda," said Geevarghese, who said activists would be disappointed by Kaine or Vilsack.
But with polls showing most Sanders supporters now falling in line for Clinton, a Sanders/Warren-wing VP pick may be less valuable.
And earning those progressive bona fides has given Perez some battle scars and turned him into a bit of a lightning rod.
Iain Murray, the vice president of the conservative Competitive Enterprise Institute, told National Review that Perez is "possibly the most dangerous person in the administration."
Senate Republicans held up Perez's confirmation to head the Labor Department for months, with Leader Mitch McConnell calling him "a committed ideologue." No Republican ended up voting to confirm Perez.
That kind of criticism could be damaging as Clinton tries to draw a contrast with Donald Trump by promoting an inclusive image (her new slogan is "Stronger Together").
Perez defenders say controversy is inevitable when taking on thorny issues others want to avoid, especially at the DOJ's Civil Rights Division, which has always been a political football.
"At the Civil Rights Division, you knew everything you did was going to get pushback from everyone," said Samuel Bagenstos, who served as Perez's deputy there. "What I saw working with him was the way he confronted these very difficult and intractable issues and really went right at the hardest questions."
And the willingness to fight tells only part of the story, they say. The other is an emphasis on building consensus between unusual allies and getting them a place where both feel like they've won.
"A lot of labor secretaries have had an adversarial relationship with the businesses community. They rail against it for not doing the right thing, and that causes executives to dig in and not really address the problems," said Darrell West, the vice president of governance studies at the Brookings Institution. "He's tried to engaged the business community about why it's in their own interest to improve the conditions of their workers."
Earlier this year, Verizon CEO Lowell McAdam said Perez had been "very helpful" in ending a strike of around 40,000 workers, which saw both Sanders and Clinton briefly joining picket lines.
McAdam even sent a letter to Obama and top White House aides praising Perez, according to a source familiar with the matter.
Last year, Perez helped to end a high-profile standoff with the labor union that represents workers at West Coast ports.
When discussing strategy with aides, Perez often invokes the model of his former boss, Ted Kennedy, who was famous for marrying a commitment to his ideals with a commitment to finding Republican allies.
"He brings to his work a real passion and deep commitment, but I think what makes him an extraordinarily leader is his ability to listen," said Rep. David Cicilline, who was in the same class as Perez at Brown University, but only got to know him years later while working together on paid family leave and other issues.
Perez keeps a portrait of Frances Perkins, Franklin Roosevelt's labor secretary, over his desk in the Department of Labor's hulking concrete building near the Capitol. He's remarked to visitors that she's the ideal all secretaries should aspire to.
The Labor Department is not the most high-profile part of the government, and Perez was passed over for attorney general after Eric Holder stepped down. But allies say Perez has used his perch in creative ways to expand his portfolio.
A vice president has not been chosen from the ranks of cabinet members in more than 75 years. This year, Clinton has considered at least three cabinet members.
It speaks to an unusual moment in the Democratic Party's history, in both ways good and bad. The good news is that the party has a popular sitting president, and are thus able to run largely on continuity. The bad news is that the party's ranks of governors and senators have been culled by two brutal midterm elections, limiting Clinton's options.
Another choice for Clinton: Does she want to double down on the party's strengths, or address its weakness?
Just as Vilsack's background makes him uniquely suited to be a party ambassador to rural areas, which are trending away from the Democratic Party, Perez probably has a better understanding than most about the issues facing cities, the Democratic Party's core.
"I think at this particular point in time, it would extremely useful to have someone like him who understands policing, who understands voting rights ... he's perfectly placed to understand all of these issues we're experiencing," said Ari Berman, the author of "'Give Us the Ballot," a history of the voting rights movement.
"You don't always want to get phone calls from federal officials when you're a mayor, but you do when it's Tom Perez," said St. Paul, Minnesota Mayor Chris Coleman.