By the time Donald and Melania Trump had their first dance at an inaugural ball Jan. 20, President Trump had two Cabinet members in place. Nearly two weeks into his presidency, he has six. (His pick for secretary of state, Rex Tillerson, was sworn in Wednesday evening after Senate approval on a mostly party-line vote.)

That's a historically low number for a president's first few weeks in office, and if the pace doesn't pick up, Trump's government is in danger of being historically understaffed.

Trump's thin Cabinet is not for lack of trying. He had nominated much of his Cabinet at a historically quick clip, and Senate Majority Leader Mitch McConnell (R-Ky.) had hoped to have up to seven of those nominees in place hours after Trump took the oath of office, which would be on par with past presidents.

McConnell's optimism was buoyed by simple math: Republicans control the Senate by a margin of 52-48 and Democrats can no longer filibuster Cabinet nominees, or require 60 votes to pass instead of a simple majority.

Democrats' only option to oppose Trump and his conservative Cabinet is to delay the inevitable. This week, it's clear that's exactly what they've decided to do. They've asked some nominees back for more questions. They've requested second hearings. They've even refused to vote on some of them.

On Tuesday and Wednesday Senate Democrats walked out on committee hearings for three separate nominees, forcing Republicans to delay the hearings — or just suspend the rules for a quorum and push through the nominees. Democrats said the nominees hadn't sufficiently answered their questions about conflicts of interest or where they stand on Trump's controversial travel ban.

Republicans accused Democrats of being sore losers. The normally even-keeled Sen. Orrin Hatch (R-Utah), chair of the Senate Finance Committee where Democrats boycotted Trump's nominees to run the Treasury Department and Health and Human Services, said Democrats "ought to stop posturing and acting like idiots."

Democrats boycott Senate hearing for Mnuchin, Price (Peter Stevenson/The Washington Post)

Things could get worse before they get better. Right now, Senate Democrats are also leaning toward filibustering Trump's Supreme Court pick, Judge Neil Gorsuch. To filibuster would be to lay the tripwire for Republicans to "go nuclear" and get rid of the minority party's ability to require 60 for votes on all political and judicial nominations. (Senate Democrats got rid of the filibuster lower-court nominees and Cabinet members back in 2013.)

Blowing up the filibuster would take up a ton of time and energy in the slow-moving Senate and basically put all these other nominations on hold.

Even if Trump's nominees get through before the Supreme Court battle, they could adopt the delay-as-resistance tactic on everything else, as a former top aide to retired Senate Minority Leader Harry Reid (D-Nev.) urged Senate Democrats to do:

"Because every Senate action requires the unanimous consent of members from all parties, everything it does is a leverage point for Democrats," wrote Adam Jentleson in a Washington Post op-ed. "For instance, each of the 1,000-plus nominees requiring Senate confirmation — including President Trump’s Cabinet choices — can be delayed for four days each."

That notion has Republicans incredibly upset.

“We need to, sort of, grow up here and get past that,” McConnell said on CBS's “Face the Nation” earlier this month.

McConnell has some historical precedent to back up his point, said Robert David Johnson, a history professor at Brooklyn College.

On his first day in office, President Jimmy Carter had eight of his Cabinet nominees confirmed.

Within two days of his inauguration, Ronald Reagan had 12 of his nominees in place.

Within 24 hours after his inauguration, Bill Clinton had 13 in place.

Even President George W. Bush, whose transition period was swept up in a dramatic Supreme Court decision about his election, had seven of his nominees confirmed on Jan. 20, and four more in four days.

President Obama — as Republicans are pointing out — had seven in place by the time he and Michelle Obama had their first dance.

Johnson says the only historical comparison to Trump's thin Cabinet on day one could be President George H.W. Bush, who had zero nominees confirmed on his first day.

Bush's problem was that he was facing a Senate controlled by the other side. Then-Senate Majority Leader George Mitchell (D-Maine) was drawing out Bush's nominees to, “send a message” that the Senate is a place to be reckoned with, Johnson said.

The fact Trump is starting his presidency with so few Cabinet members in place underscores just how partisan pretty everything in Washington has become. For most of this century, there was little to no political drama surrounding nominees. Now, it could take months for Trump to have his team in place.

Eventually, though, Trump will have his Cabinet. No matter how long Democrats delay, they can't actually stop these picks from being approved. As Sen. Johnny Isakson (R-Ga.) said recently: "The ultimate result was not in doubt. Getting to the ultimate was in doubt."