The 119th Congress convenes on Friday amid a huge shift of power in Washington as Republicans take control of both chambers of Congress ahead of President-elect Donald Trump being sworn in on Jan. 20.

The first order of business in the House will be to elect its speaker — a process that has created high drama in recent years.

Republicans maintained control of the House in the November elections, but will hold a historically narrow margin. Speaker Mike Johnson of Louisiana appears to have the support of the majority of his conference — and the endorsement of Trump and Elon Musk, the billionaire donor who has been advising the president-elect. But it’s not necessarily locked in that Johnson will secure the gavel on the first ballot. GOP Rep. Thomas Massie of Kentucky has said he will vote against Johnson, meaning Johnson can only afford one more defection from his conference. At least 17 Republicans say they are undecided, by an ABC News count.

House Democratic Leader Hakeem Jeffries has said Democrats won’t help Johnson get elected.

How is the speaker elected?

Johnson will need a majority of those present and voting to remain speaker. That means the number starts at 218. The official majority will be determined after the opening of Congress; the clerk reads the official number of certificates of election received and that is used to determine a majority and members record their presence during a quorum call.

The simple majority can change depending on any absent members or if members vote “present” — which would lower the threshold needed.

Former Republican Rep. Matt Gaetz, who resigned from Congress in November after Trump picked him to be his attorney general before later withdrawing, is the most intriguing wild card.

Gaetz has toyed with the prospect of returning to the Capitol to participate in the speaker’s vote and create one last dose of congressional chaos. The House Ethics Committee released a report on its investigation into Gaetz over violations of House rules after he left the House, but he was reelected in November before resigning.

If Gaetz doesn’t return on Friday, which is the likely scenario, then the total number of the House will be 434 members with 219 Republicans and 215 Democrats. This means, Johnson cannot afford to lose more than one defection — a second would block him from getting the gavel.

Democratic Speaker Emerita Nancy Pelosi, who underwent hip replacement surgery in December, posted on X that she will be at the Capitol for the speaker vote.

What happens if Johnson loses the vote?

The House will continue to vote until a speaker is elected because without one, it can’t conduct any business, like certifying Trump’s presidential election results on Monday. The House could vote on a resolution to approve a speaker by plurality — the most votes of any given candidate. But this could be dangerous for Republicans and is unlikely. All Democrats are expected to vote for Jeffries.

Normally, the opening day in the House lasts roughly 2 1/2 hours. However, after the way things went two years ago when it took Kevin McCarthy 15 rounds of voting to become speaker, anything is possible.

Here are other times the House has struggled to elect a speaker:

2023: McCarthy was elected on the 15th try. Months later he was ousted by Gaetz and seven other Republican members.

1923: Fredrick Huntington Gillet became speaker after nine rounds of votes. That may sound like a lot, but the longest running contest was…

1856: Nathaniel Prentice Banks of Massachusetts had served just one term in Congress. Upon reelection as a member of the American Party, he was elected speaker after 133 ballots — a process that took nearly two months, according to the House Historian.

1849: The House was in session 19 days without being able to elect a speaker, with no candidate having received a majority of the votes. Finally, after the 59th ballot, the House adopted a resolution declaring that a speaker could be elected by a plurality.

Does the speaker have to be a member of Congress?

No. The Constitution does not dictate that the speaker be a member, either current or former. In fact, the speaker is supposed to lead the whole House, not just one party. Some Republicans have suggested Musk as speaker.

Today’s schedule in the House

Noon: House gavels in, holds a recorded quorum call.

12:45-1 p.m.: Speaker election begins.

TBD: Swearing-in of members and delegates after a speaker is elected.

TBD: Adopting rules package of 119th Congress.

On the Senate side

Unlike the House, Senate leadership is already set ahead of Friday. And though the new Congress is certain to bring with it a host of big moments — a new Republican majority, spearheaded by a new Republican leader, as Sen. John Thune of South Dakota replaces Sen. Mitch McConnell of Kentucky.

Friday’s schedule in the Senate

Noon: The Senate is gaveled in.

Opening prayer and Pledge of Allegiance: Led by the Senate Chaplain. The current Chaplain, Barry Black, was hospitalized in mid-December due to a brain bleed. It’s unclear whether he or another designee will lead the opening prayer.

Swearing-in of senators: Typically any senator who won election in November will be sworn in to a new term — whether a newly elected member or a returning incumbent. They typically take the oath in groups of four. Each senator who is being sworn in will have an escort with them, who is typically a current or retired senator. Many senators will choose their fellow home state senator as an escort but this is not required — some choose friends or mentors.

Signing of the oath book: After the senators take the oath, each will sign their name in the oath book at a designated place.

Establishment of a quorum and adopting organizing resolutions: After the members are sworn in, you’ll hear a request from the majority leader to establish a quorum. We expect this to be Thune in his capacity as party leader. The clerk will read the roll of the entire new Senate.

The first order of business is typically the adoption of a resolution that informs the president that the Senate is in a quorum and ready to receive any communications from him. A similar resolution is issued to the House. Next, the president pro tempore is appointed via a resolution. The longest-serving member of the majority party typically receives this honorary role, in this case Grassley. After the resolution is adopted, we expect Grassley to take over from Harris to guide the Senate through the adoption of additional organizing matters.

Then there will be a unanimous consent request to pass a block of organization resolutions. Among those is a resolution establishing committees and another establishing operating rules of the Senate. Because these things are worked out between the party leaders beforehand, these resolutions are almost always swiftly unanimously adopted with little fanfare.

Leader speeches: We will hear speeches from both party leaders – Thune, for the first time, and Democratic Leader Chuck Schumer of New York.

Ceremonial swearing-in: After the officially swearing in on the floor, senators will head to the old Senate chamber to reenact the swearing in for a photo op with the vice President. Their families typically join them.

Some highlights in the Senate

History-making Black women: When Lisa Blunt Rochester and Angela Alsobrooks are sworn in, they’ll be the first two Black women to serve in the Senate at the same time.

More history: After he’s sworn in, Sen. Tim Scott of South Carolina will become the longest-serving Black senator. Scott will also become the first Black chairman of a Senate standing committee when he assumes the chair of the Banking, Housing, and Urban Affairs Committee. Scott will be serving his third term.

And yet more history: The 119th Congress will see the first time five Black senators have served concurrently – Alsobrooks, New Jersey Democrat Cory Booker of New Jersey, Blunt Rochester, Scott and Democrat Raphael Warnock of Georgia.

Kamala Harris’ final functions: As the current vice president, the 2024 Democratic presidential nominee will be responsible for the swearing-in of the new members. It will be one of Harris’ last responsibilities as VP, aside from Jan. 6 and the inauguration.

Chuck Grassley resumes role as President Pro Tempore: Chuck Grassley is 91 years old and with Republicans back in control will return to the role he served in from 2019 to 2021. Grassley was first elected to the Senate in 1980 and has been reelected seven times.

No Jim Justice (or Babydog, for that matter): Sen.-elect Justice announced at a press conference last week that he will resign as West Virginia’s governor on Jan. 13, just before Gov.-elect Patrick Morrisey is sworn in to maintain continuity in his home state. We’ll have to wait a bit longer for him and his famous bulldog to take the oath.

Adam Schiff and Andy Kim get re-sworn in: Unlike the rest of the freshmen class, Sens. Andy Kim and Adam Schiff were sworn in on Dec. 9 after having won election to fill seats that were previously occupied by governor-appointed placeholders. We expect both to be re-sworn in.

Who’s in, who’s out?

Here are new senators and who they’ll replace:

• Angela Alsobrooks, D-Md., replaces Democratic Sen. Ben Cardin, who retired.
• Rep. Jim Banks, R-Ind., replaces Republican Sen. Mike Braun, who retired.
• Rep. John Curtis, R-Utah, replaces Republican Sen. Mitt Romney, who retired.
• Lisa Blunt Rochester, D-Del., replaces Democratic Sen. Tom Carper, who retired.
• Rep. Ruben Gallego, D-Ariz., replaces independent Sen. Kyrsten Sinema, who did not seek reelection.
• Jim Justice, R-W. Va., replaces independent Sen. Joe Manchin, who retired.
• Former Rep. Andy Kim, D-N.J., replaces Sen. George Helmy, who completed former Sen. Bob Menendez’s term after he resigned. Helmy did not seek election.
• David McCormick, R-Penn., replaces Democratic Sen. Bob Casey, who lost his reelection bid.
• Bernie Moreno, R-Ohio, replaces Democratic Sen. Sherrod Brown, who lost his reelection bid.
• Former Rep. Adam Schiff, D-Calif., replaces Democratic Sen. Laphonza Butler, who was appointed to finish former Sen. Dianne Feinstein’s term. Butler did not seek election.
• Tim Sheehy, R-Mont., replaces Democratic Sen. Jon Tester, who lost his reelection bid.
• Elissa Slotkin, D-Mich., replaces Democratic Sen. Debbie Stabenow, who retired.