Kings of the hill (and the white house).

• Author: Smith, Patricia
• Position: Cover story

President Trump is moving ahead with his agenda, with help from a Republican-controlled Congress. But the system that the Framers designed gives the Democrats in the minority some power of their own.

When American voters chose Republican Donald Trump as the 45th president in November, they also handed his party control of Congress. Republicans maintained a majority in the Senate, with 52 seats to 48 for Democrats. In the House of Representatives, Republicans increased their majority to 241 to 194 for Democrats. But having one political party control the White House and Capitol Hill doesn't mean it will be able to pass laws at will.

"The Framers designed a system with extra checks to protect the voices of the minority against what they called 'the tyranny of the majority,'" says Costas Panagopoulos, a political scientist at Fordham University in New York.

To make matters more complicated, President Trump comes into office with an unclear mandate. He won the Electoral College decisively, 306 to 232, but he lost the popular vote by almost 3 million votes. It remains to be seen how forcefully Republicans in Congress will support his agenda and translate his proposals into law--and how hard Democrats will battle against Trump's plans.

Here's what you need to know to follow the action in Washington as Trump begins his four-year term.

What does control of the White House and Congress mean?

It means Republicans will set the agenda in Washington. President Trump will lay out his legislative priorities and work with Republicans in Congress to get them passed. Because they're in the majority, Republicans control committees in Congress, which is where a lot v of important decisions about bills--including whether they even get voted on--are made.

In short, Republicans will have enormous sway over the lawmaking process. And whatever bills Congress approves are likely to be signed when they reach the president's desk.

That's good news for Trump. Some of his priorities--like repealing Obamacare and reducing taxes on business--are likely to move through Congress quickly.

"They're going to do big, hard things right out of the gate," says Douglas Brinkley, a presidential historian at Rice University in Texas.

Does that mean Republicans can do whatever they want?

Not necessarily. In the 435-member House, legislation needs a simple majority of votes to pass. But in the 100-member Senate, the filibuster rule means that 60 votes are required for most bills to...