In the early days of Tom Perez's stewardship at the Democratic National Committee, he first met in 2017 with a small cadre of Hillary Clinton campaign staffers, who were fresh off a devastating loss to Donald Trump, to chart a path forward for the party committee that struggled for much of the 2016 cycle.
Among those in the conversations with the new chair and senior leadership at the DNC -- which stretched over the course of the 2020 cycle and included an in-person meeting in October 2019 -- was Robby Mook, Clinton's campaign manager for her 2016 bid, who offered his thoughts on the DNC's most cardinal role within the party. He argued for setting up a campaign-in-waiting, he recalled, to reinforce a nominee's fledgling campaign with data infrastructure to compete with the GOP, more robust field organizing resources for once the primary concludes and more deliberate coordination with state parties.
"The hard part about being a chair is a million people are going to come to you telling you to do a million things," Mook said in an interview on Wednesday. "But at the end of the day, the most important thing that only you can do is to build an infrastructure ... only (Perez) can do that."
Nearly four years later, the DNC is in a far different position than it was in the aftermath of the 2016 election, having successfully buoyed the triumphant campaign of the party's standard-bearer, Joe Biden. Still, Democrats face challenges ahead as they confront a splintered reality that reflects much of the country's deep divisions.
The party is reveling in President-elect Joe Biden's "decisive" victory over Trump, as Perez put it, yet it is also grappling with a series of down-ballot losses, in which Democrats in crucial House and Senate races fell short, leaving Trumpism within the halls of Congress.
"The thing about 2018 is we were able to win in states, in races, that were deep Trump territory," Perez told ABC News on Thursday. "We always knew in 2020 it was going to be tougher to win those races."
A complete turnaround from 'dysfunction'
In the aftermath of this year's election, Democrats are still sorting through the ideological fissures that have defined the party for most of the cycle, most prominently during the Democratic primary when the presidential contenders of the party's left pushed progressive policies on issues from health care to climate change into the debate.
But unlike four years ago, or even one year ago, Democrats now have the White House and at least one chamber of Congress in their grip -- a near opposite outcome that defined 2016.
"The Democratic Party was on the ropes," Sam Cornale, the deputy chief executive officer at the DNC, said of 2016.
The political operation, too, was in disarray for much of the last presidential race over email leaks and criticisms of a rigged nomination fight, or as Perez candidly described as "dysfunction."
"Hillary Clinton was handed a really lousy infrastructure," Perez said, adding that he took over a "skeleton crew" from his predecessors. "It was a turnaround job ... and involved making sure that we were rebuilding our infrastructure top to bottom and rebuilding trust."
Perez, a former labor secretary under President Barack Obama, formally assumed the title in February 2017 after Congresswoman Debbie Wasserman Schultz, D-Fla., whose tenure at the helm of the DNC was riddled with controversy, abruptly resigned, leading to the appointment of longtime Democratic hand Donna Brazile as interim chair.
Under his leadership, the party apparatus has actively worked to implement those early recommendations, heavily prioritizing the behind-the-scenes, fundamental aspects of a campaign, such as operations and data investments, to complement the campaign of the eventual nominee.
"(It) was real nuts-and-bolts stuff, that ain't sexy, but is so, so important," Perez said.
In touting the party's achievements throughout the cycle, Perez pointed to their battleground program, which consisted of some of the earliest investments in field operations; a voter protection program, which involved a deep bench of organizing, operations and data staff across 33 states to combat voter suppression; overhauling the party's technology infrastructure, which included building a data exchange of voter information with party allies and outside groups; and ensuring a fair primary after significant reforms to the nominating process.
The institutional changes were, in part, a response to the deficiencies during Clinton's run. The procedural reforms, such as reducing the influence of superdelegates, came after a bitter 2016 primary between Clinton and Sen. Bernie Sanders, I-Vt., during which Wikileaks released a trove of internal emails from the DNC, which showed some top party officials appearing to aid Clinton's campaign during the primaries, including disparaging emails from Wasserman Schultz while she was chairwoman, about the Sanders campaign.
Back in July, Larry Cohen, a longtime ally of Sanders who is also chair of Our Revolution, a nonprofit political organization aligned with Sanders, said the 2020 primary season was "night and day," compared to 2016.
From inside the party structure, the election this year may have resulted in some lost ground down-ballot, but a summation of Perez's tenure marked by persistence and key investments in infrastructure show a DNC in far better shape than four years ago.
"We are going to and should be judged by the strength of the party we're handing off and the very notion that we not only won back the House in 2018, but that we're competitive in beet red districts to me actually underscores how strong this party now is," said Cornale.
The DNC's risky bet
One of the Democrats' most successful turnarounds was in the money race, particularly after Clinton's withering critique about inheriting a "bankrupt" committee.
"I get the nomination. So I'm now the nominee of the Democratic Party. I inherit nothing from the Democratic Party," she said during an appearance at the Code Conference in 2017. "It was on the verge of insolvency, its data was mediocre to poor, nonexistent, wrong. I had to inject money into it."
Democrats closed out the final months of the 2020 campaign outpacing the Trump team's fundraising and stockpiling cash. In September, Biden and the DNC raked in about $135 million more than the Trump campaign and the Republican National Committee, and ended the month with nearly twice as much in their coffers.
But the DNC's fundraising trajectory was not always a given.
"I wasn't sure we were going to have the money. I was prepared if necessary to take out a loan to make sure we can meet that commitment," Perez said. "We didn't have to take out a loan at the end of the day."
One party aide told ABC News that around this time last year, when the DNC's financial health was less certain, particularly as the Democratic primary was far from settled, the committee moved forward with outlays in key battleground infrastructure. It was a risky move as their debt stood in the millions.
At that point, national Democrats were spending as much as they were raising, leaving less than $10 million in the bank, with $6.5 million owed in debt.
Even in the first month of joint fundraising with Biden, they landed more than $180 million behind the Trump campaign and the RNC in cash on hand and were weighed down by more than $5 million in debt. It wasn't until May that the Biden and Democrats outraised their Republican counterparts for the first time.
The partnership with the Biden campaign, the DNC chief asserted, stands as a model for elections to come.
"I think we have really written in the 2020 cycle a really good playbook of how a presidential campaign and a campaign committee come together ... to win elections and to unseat an incumbent president, (which) happens about once every 25 years. This is a tall order," he said.
"Our teams worked together as one, taking advantage of the critical groundwork laid by the DNC and local organizers to build strong and extensive infrastructure that helped us rebuild the blue wall and win states across the country this cycle," said Jenn Ridder, the states director for the Biden campaign, in a statement. "Together, we brought home a victory for Democrats, and Americans of all stripes, across the nation."
The path ahead
But Democrats' fight is still not over.
Asked how the DNC plans to extend their efforts throughout the 2020 campaign into overtime, with Georgia holding two runoffs in early January that could decide the balance of power in the Senate, Perez leaned into the party's "fusion coalition" that turned the Peach State blue for the first time in a presidential election in nearly three decades.
"There's a direct through line between their participation and victory," he said. "It's about continuing to expand the electorate, continuing to make the case that you can make a difference because you just did make a difference."
Despite Democrats historically performing poorly in statewide runoffs -- and the fact that losing just one of the two seats hands the GOP the majority -- the party remains confident in their chances, arguing that Republicans have not historically competed well in any elections without Trump on the ballot, Cornale said.
For his own path forward, Perez is less sure.
"I have no idea what I'm doing next because I have spent no time, or next to no time, thinking about it because I really spent all of my time making sure we sprinted across the finish line here," Perez said, without endorsing a successor.
ABC News' John Verhovek and Soo Rin Kim contributed to this report.