Each nomination presents Democrats an opportunity to litigate arguments that have been at a boiling point throughout the election on a public stage, their first chance to stand up to a President that outgoing Senate Minority Leader Harry Reid called "a sexual predator who lost the popular vote and fueled his campaign with bigotry and hate" in a statement after his election.
Even if Trump won, Democrats can argue, his agenda is out of touch.
Anti-big bank Democratic Sen. Elizabeth Warren on Wednesday called Trump's Treasury secretary nominee, fundraiser and former Goldman Sachs partner Steven Mnuchin, the "Forrest Gump of the financial crisis."
Incoming Senate Minority Leader Chuck Schumer said the nomination of Georgia Rep. Tom Price for Health and Human Services signaled a "war on seniors" and pledged to "fight tooth and nail" for Medicare.
The eight Democrats on the Judiciary Committee sent a strong letter saying they want several days of hearings on attorney general nominee Jeff Sessions, including testimony on issues such as violence against women, LGBT protections, civil rights and hate crimes.
Fighting Trump's agenda is pretty much the Democrats' only option when it comes to Cabinet picks.
Thanks to a rule changed pushed by Democrats during the Obama administration, all nominees except Supreme Court picks are only subject to a simple majority vote -- and Republicans have the majority. In addition, lawmakers have often given deference to a new president, saying he has the right to choose his Cabinet and advisers -- to a point.
Pressure from the left versus working with Trump
Democrats will be under competing pressures once the new Congress begins in early January and hearings for the top-tier Cabinet posts begin.
On the one hand, the progressive base will be eagerly watching to see how aggressive Democratic senators are in going after Trump's emissaries. But Democrats will have to work in Trump's Washington moving forward -- including with the various Cabinet members they interview. And some moderate senators, like West Virginia's Joe Manchin, are also up for re-election in two years in states that Trump won.
Progressives will be watching how Democratic members handle the spotlight, said Symone Sanders, an activist and former press secretary for Bernie Sanders' presidential campaign.
"The confirmation hearings are the first battle, the first test if you will, of Democrats in the Trump era," Sanders said. "And they have the potential to come out with flying colors."
"They have to demonstrate a show of force during these hearings and making sure they don't let the conversation get away from them," she added. "Because if it looks like Democrats are rolling over for Donald Trump and Republicans, it's not going to bode well for midterms."
Race will be a flashpoint
in the hearings for attorney general nominee Sessions, who has represented Alabama in the Senate for nearly 20 years.
Sessions failed to get confirmation as a federal judge in the 1980s over concerns
about some of his statements on race relations. While he has served in the Senate alongside the members who will be questioning him for decades, his past is sure to come up again as the election has reopened racial wounds in the US. As attorney general, Sessions would oversee the civil rights division of the Justice Department, have a lead role in issues of police violence around the country, and be heavily involved in enforcement of immigration laws.
Price has been one of the chief critics of Obamacare in Congress and a proponent of overhauling Medicare, both of great concern for Democrats. His hearing will give Democrats their first opportunity to fight to save as much as they can of President Barack Obama's signature health care law and entitlement programs.
Trump's pick for the CIA, Kansas Rep. Mike Pompeo, is sure to face questions from Intelligence Committee Democrats about his past statements in favor of expanding US surveillance and of Trump's own praise of torture techniques like waterboarding, especially with fierce surveillance opponent Oregon Sen. Ron Wyden on the panel.
Mnuchin represents big banking to progressive Democrats like Warren and independent Vermont Sen. Bernie Sanders who have built a massive grassroots following for their anti-Wall Street message. His involvement with troubled mortgage lender IndyMac will raise the specter of the housing crash.
And Commerce pick Wilbur Ross is a billionaire nicknamed the "king of bankruptcy" for buying up distressed companies for turn-arounds.
Each nominee goes before different committees with jurisdiction, spreading opportunities for Democrats to grill Trump's Cabinet.
All of them will likely get heavy scrutiny of their financial disclosure forms, says Stephanie Martz, a lobbyist with Monument Policy Group who spent years in the Senate with Schumer and worked for the Obama administration. That is especially true if Trump's own conflict of interest questions are not resolved cleanly enough for Democrats by that point.
She expects Democrats to take their opportunities to be tough.
"Everyone is going to take the opportunity to get real answers from nominees who have said or done things in the past that may raise questions, but also lay down markers about what they're going to be watching, because besides cloture, is very hard to block these nominees," Martz said.
But Martz also cautioned that nominees will help set the tone of hearings, and if they don't misstep, the tenor could remain calmer.
"Senators can be pretty vicious if they want to be," she said. "But I think it's harder than it might seem when there's a nominee sitting there facing you and their whole family and friends are arrayed behind them, it's hard to get truly personal and nasty with that person. Obviously, it can happen, especially if the nominee is not particularly friendly and is kind of combative in the way he or she answers questions, it can kind of go downhill."