Republicans win the House, completing their 2024 election 'trifecta.' What total control on Capitol Hill will mean for Trump's presidency.

More than a week after winning the presidency and the Senate, Republicans have finally completed the so-called trifecta and secured the 218 seats required for control of the U.S. House of Representatives. The AP declared the majority for the GOP Wednesday night.

But just barely. A handful of races remain uncalled, and when the dust settles in the days ahead, the GOP could end up with only the slimmest of majorities.

Here’s what that will mean for Donald Trump’s second term.

First, Republicans will have at least 52 seats in the next Senate. (If the hedge-fund executive David McCormick wins in Pennsylvania — where he currently leads by half a percentage point — they will have 53.) With that majority, the GOP will be able to confirm all of Trump’s judicial nominees, including younger Supreme Court justices who could ensure conservative control of the court for decades to come. They’ll be able to confirm Trump’s Cabinet officials as well.

Second, without control of the House, Democrats won’t be able to continue investigating the Trump administration the way they did from 2019 to 2023 (when they probed Trump’s allies’ ties to Russian interference in the 2016 election and the scheme to overturn his 2020 loss). And they won’t be able to impeach him again, either. Control of the House will now allow Republicans to chair committees and launch their own investigations.

The bigger question is how much legislation Republicans will pass, and how far that legislation will go. And that, in turn, depends on the size of their House majority, the composition of their leadership and the ambition of Trump himself.

During the 2024 campaign, Trump focused less on his congressional agenda than on things he could do on his own: imposing huge tariffs on foreign goods, deporting millions of immigrants, rethinking the United States’ commitment to NATO and allowing Russia to annex parts of Ukraine.

He will probably have the power to implement those policies, regardless of whether the House and Senate agree with him.

To pass new laws, however, he will have to get votes in Congress.

The first bills Republicans will try to pass will probably be those that can squeak through without any Democratic support (i.e., the ones that qualify for the process called budget reconciliation, which requires only 51 Senate votes for measures related to taxes and spending). So expect an early push to extend tax cuts for the wealthiest Americans and slash taxes for corporations.

Republicans could possibly unravel the Affordable Care Act and crack down on the border through reconciliation as well, ideas that senators such as Tom Cotton of Arkansas and Lindsey Graham of South Carolina are already discussing. Trump also wants to eliminate the tax on tips, overtime and Social Security benefits for seniors.

Yet any policies that don’t involve taxes and spending still need a filibuster-proof Senate majority of 60 votes to pass — and Republicans won’t have 60 votes.

One big factor, then, is whether Republicans will eventually push to end the legislative filibuster (after deciding in 2017 to end the filibuster for Supreme Court nominations). So far, Senate Minority Leader Mitch McConnell of Kentucky has said the filibuster is "very secure." But South Dakota Sen. John Thune will replace McConnell when the new Senate is sworn in next year. Will Thune continue to uphold the filibuster under pressure from Trump and MAGA lawmakers who are eager for sweeping change?

If not, and if the filibuster falls, there would be little to stop a GOP trifecta from implementing Trump’s most controversial plans — other than congressional Republicans themselves.

That isn’t outside the realm of possibility. During Trump’s first term, conservatives such as House Speaker Paul Ryan checked the president’s ambitions; recently, House Republicans have struggled to keep their narrow majority unified amid challenges from the hard-right Freedom Caucus.

When the margins are as slim as they are likely to be next year — two or three votes in the Senate; maybe four or five votes in the House — individual senators and members suddenly have a lot of leverage. A small number of defections can sink any bill. Moderates such as Alaska Sen. Lisa Murkowski and Sen. Susan Collins of Maine, not to mention the dozens of representatives from centrist swing districts, become pivotal. The same goes for right-wing House rebels.

With Trump back in the White House, will a Republican Congress be more emboldened — and more united — than before? Or will Trump push too hard and get some unexpected pushback from his own party?