President-elect Donald Trump and Vice President-elect Mike Pence disembark from Trump's plane as they make their way to Carrier Corporation in Indianapolis on Dec. 1, 2016. (Jabin Botsford/The Washington Post)

When Mike Pence journeyed to the Capitol this week, House Speaker Paul D. Ryan flubbed his introduction — presenting him to lawmakers as “Vice President-elect Trump.”

Ryan could be forgiven for confusing the two men and their roles. The first week of the 115th Congress has been a tale of two administrations, full of jarring reminders that there will be two distinct managers working at the White House — and probable tensions between their contrasting styles.

Ensconced in his gilded Manhattan tower earlier in the week, Trump sent House Republicans reeling with a duo of tweets — just four minutes apart — that criticized his party’s controversial decision to decimate an independent congressional ethics office. Lawmakers, already under siege from their constituents, quickly reversed themselves.

But a day later, Pence headed to Washington with a decidedly humbler mission. Nestled in a windowless basement room in the Capitol Building, he spent more than an hour listening to the parochial concerns of House lawmakers, nodding along as rank-and-file members talked about Western land use and the minutiae of health policy.

(Peter Stevenson/The Washington Post)

The dueling interactions of Trump and Pence with Congress offered an early preview of how the incoming White House may attempt to alternately strong-arm, cajole and tweet Congress into submission.

Perhaps most vulnerable to the dynamic are the relationships between Trump and Ryan (R-Wis.) and Senate Majority Leader Mitch McConnell (R-Ky.). Already enacting a robust domestic agenda, the two leaders are busy corralling their own members, and allies say they are not eager to devote extensive time to managing the caprices of Trump.

Enter Pence, who made clear in his visit to the House and in remarks to the midweek Senate Republican luncheon that he will seek to be an accessible and stable force at the Capitol. Pence’s “genteel” dealings with Congress, as one Republican described it, are also expected to run deep on policy, and a top Pence aide was installed this week as Trump’s legislative director.

“There are many ways to disrupt. One is the power of the tweet. Trump’s got that down,” Sen. Bill Cassidy (R-La.) said. “The other is by the power of policy. Pence has that down.”

Trump advisers describe the relationship between Trump, Pence and Capitol Hill as symbiotic, if unconventional.

“Yes, they are different people and they have different approaches, but the vice president-elect understands that it is the president-elect’s agenda,” said Sean Spicer, the incoming White House press secretary.

President-elect Donald Trump comes to Capitol Hill to meet with Senate Majority Leader Mitch McConnell (R-Ky.) on Nov. 10. (Bill O'Leary/The Washington Post)

“It’s not like he wanted a clone,” Spicer said.

In many ways, Trump and Pence are relocating their campaign trail act to the nation’s capital — a WWE tag team, a good cop-bad cop routine and, in the words of several Republicans, a marriage of opposites.

“You see this in a lot of marriages; you each bring strengths to a relationship, different qualities,” said Sen. Deb Fischer (R-Neb.), comparing Trump and Pence to her and her husband, who have been married nearly 45 years. “You balance each other out. I think the two of them have that figured out, and it seems to be working out.”

And Rep. Chris Collins (R-N.Y.), a member of Trump’s transition team, said, “It’s a great marriage of two individuals since Pence’s role is clearly the legislative, administrative guy to get things done so we can put bills on Trump’s desk.”

Yet the union could also yield two rival, or at least incongruous, power centers, with Pence operating in some ways as a shadow president.

The vice president-elect, after all, presents as a more conventionally conservative Republican, who understands and respects the arcane levers of governing — the sort of leader with whom congressional Republicans feel ideologically and temperamentally comfortable.

Trump, meanwhile, offers a rifle-shot approach — erratic, scattered, unpredictable. Unlike Pence, who can delve deep into policy details, Trump has largely concerned himself with two broad areas: foreign policy and job creation.

“We know there are going to be times where we have more access to Pence than Trump,” said Sen. Ron Johnson (R-Wis.), a former businessman who said Trump reminds him of executives who delegate responsibilities.

So far, most Republicans have argued, the Trump administration’s opening salvos have been effective. Trump’s tweets were part of the push on House Republicans to stand down on their ethics overhaul. And Pence helped reassure skittish Republicans who had been nervous about Trump — leading a “private pep rally,” as Rep. Walter B. Jones (R-N.C.) recounted the meeting — and providing a basic blueprint for Trump’s plan to repeal President Obama’s Affordable Care Act.

Many Republican lawmakers are optimistic that Trump could shake up Washington’s often stagnant bureaucracy. “It doesn’t have to be like it’s always been,” Sen. Roy Blunt (R-Mo.) said.

Some Democrats are also cautiously hopeful, thinking that they have found a willing negotiating partner in Trump, who is not particularly ideological. Still, Democrats are unsure how the power dynamic will unfold, given that Trump and Pence’s views may sometimes contrast on big issues.

“Pence, in many ways, we know,” said House Minority Whip Steny H. Hoyer (D-Md.). “We served with Pence. We know him. He’s predictable. He and I have a lot of disagreements, ideologically, but we know each other personally and get along personally. So, to that extent, one could say it’s easier to work with Pence.

“But Trump tends to be pretty transactional. He’s not the kind of person who comes down on a certain ideological side of most issues. It’s all about how he feels today, and maybe he won’t feel the same way tomorrow. Because he’s not ideologically driven, it may be easier to deal with Trump.”

Sen. Jeff Flake (R-Ariz.), who has clashed with Trump, declined to say how Trump’s tweets could potentially damage fragile agreements and sensitive relationships.

“Pence is diplomatic, careful,” Flake said, before struggling to describe Trump. “Trump is about the overall message. I hope for the best and am moving ahead.”

Among the many uncertainties is whom to trust.

“Let’s face it: People will step out thinking they know what Trump’s thinking, and they don’t, and they make a statement that is contradicted with a tweet the next day, and it’s, ‘Oops, I guess I didn’t read the tea leaves correctly,’ ” Collins said. “But Donald Trump is doing what’s best for the country, and he’s not going to lose any sleep over it.”

Another question is whether Trump will continue to alternately berate and appeal to his rivals. On Thursday, Trump called Senate Minority Leader Charles E. Schumer (D-N.Y.) a “head clown” in a tweet, only to moments later urge Democrats and Republicans to “get together and come up with a healthcare plan that really works.”

Congressional leaders, such as House Majority Leader Kevin McCarthy (R-Calif.), reject the notion that they can primarily work with just one camp or the other. If everything — sweeping policy changes, messaging, party unity — is going to coalesce, they say they’ll need to draw from both Republicans’ styles.

“The word I’m using around here, talking to members, is ‘synergy,’ ” McCarthy said. “That’s how we’re going to work with them and how they’ll work together.”

He noted that House Republican leaders have provided office space for Pence on the House side to encourage a close relationship with the chamber — an unusual offering for a vice president, who is formally part of the Senate and keeps an office there.

Asked if Trump, too, would have an office on the House side, McCarthy paused and then just chuckled.