As the 115th Congress is sworn in Tuesday, Republicans will be poised to control Washington with a stronger hand than they have in a decade — with the Senate, House and the White House in GOP control once President-elect Donald Trump takes office on January 20.

This past November, Republicans held their congressional losses to a minimum, helped by an unexpectedly strong GOP wave behind Trump. After losing just two Senate seats, they'll hold a 52-48 edge (two independents caucus with Democrats). In the House, Republicans lost six seats, giving them a 241-194 majority.

House Speaker Paul Ryan boasted shortly after Election Day that the "new unified Republican government" would be "focused on turning President-elect Trump's victory into real progress for the American people."

And as NPR congressional correspondent Susan Davis explained, there is precedent for a unified government pushing through sweeping changes early on:

"When the White House and Congress have been controlled by the same party, Washington has produced some of the most sweeping — albeit politically polarizing — legislation aimed at shifting the political trajectory of the nation toward the cause of the party in power.

"In particular, the first two-year congressional session of a new administration — when public approval is generally at its highest for the incoming president — has produced some recent presidents' most memorable legislative imprints."

GOP congressional leaders and Trump agree on many things — paramount among them their best chance ever to repeal and replace Obamacare, in addition to rolling back federal regulations and increasing infrastructure projects.

But there are some looming showdowns between the incoming president and members of his own party on Capitol Hill — many of whom were less than supportive of Trump in the primaries and lukewarm on his prospects in the general election.

Top Republicans have already signaled their break with Trump over alleged Russian cyberattacks intended to interfere with the U.S. elections. After President Obama announced sweeping sanctions against the country last week, Ryan called the response "overdue" but "appropriate." Senate Majority Leader Mitch McConnell said the sanctions were a "a good initial step" and reiterated his support for a congressional investigation into the supposed interference. Senate Armed Services Chairman John McCain is planning a hearing for Thursday into the breach, with three top intelligence officials set to testify.

Trump, however, has said the country should "move on" from the cyberattacks. During the campaign he repeatedly praised Russia and its president Vladimir Putin, casting doubt that they were behind the intrusion. He even praised Putin as "very smart!" after his muted response to sanctions from the Obama administration. Trump has, however, agreed to meet with U.S. intelligence officials regarding the cyber breaches this week.

Congress is prepared to get a jump start on confirming Trump's Cabinet nominees as well, with hearings on some top appointees beginning next week. But many of his most important picks are controversial, particularly Secretary of State nominee Rex Tillerson. The Exxon Mobil CEO's ties to Russia and Putin have already raised concern, and he's sure to be pressed about the new sanctions as well.

Alabama Sen. Jeff Sessions's nomination for attorney general could be contentious too. While sitting members typically receive deference from their peers, Democrats will draw attention to his past failure to get confirmation as a federal judge because of alleged racist remarks made in the past.

Another looming fight will be when Trump makes his pick for the Supreme Court to succeed the late Justice Antonin Scalia. President Obama's nominee Merrick Garland languished last year as Republicans declined to take up his nomination.

The process of repealing the Affordable Care Act is expected to get started this week as the Senate is expected to take up a budget measure that would begin the process of dismantling President Obama's signature domestic achievement. But it won't come quickly. Without a replacement plan on the table, some Republicans are wary of moving too quickly to dismantle the healthcare law for fear it would roil insurance markets if no fix is ready to be implemented.

Soon after the members of the 115th Congress are sworn in on Tuesday, their next task will be to officially re-elect Ryan as speaker. And while there's little drama expected, there could still be defections once the voice vote is held on the House floor, particularly from hardline Trump supporters. Two years ago, then-Speaker John Boehner had 25 members of his own party vote against him. When Boehner stepped down in October 2015, only nine other Republicans voted for someone other than Ryan.

Ryan distanced himself from Trump just before Election Day after damaging audio emerged of Trump bragging about groping women. The two have since reconciled, but there have been signs of discord among the base. At a rally last month in Ryan's home state of Wisconsin, the speaker was booed. And while Trump quieted the dissenters, he did caution that if Ryan ever opposed him their relationship might not be so rosy any longer.

"Honestly, he's like a fine wine: Every day goes by, I get to appreciate his genius more and more," Trump told the Wisconsin crowd on Dec. 13. "Now, if he ever goes against me, I'm not going to say that, OK?"

It may have been a joke, but speaks to the strain in the most powerful relationship in Washington.

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