Editor’s Note: Julian Zelizer is a professor of history and public affairs at Princeton University, and author, with Kevin Kruse, of the forthcoming “Fault Lines: A History of the United States Since 1974.” The opinions expressed in this commentary are his own. View more opinion articles at CNN.

CNN  — 

If anyone expected Donald Trump’s presidency to evolve into something more normal, the past few months should have disabused them of this misplaced confidence. The year ended with total political chaos: An administration under investigation on multiple fronts, several high-profile departures — one, Secretary of Defense James Mattis, in full protest of the President’s world view — and a stock market that has been plummeting.

Can 2019 top the tumultuous political year that is now coming to an end? Here are six big political questions that will shape the coming months.

How will Democrats use their power?

Now that Democrats are in control of the House of Representatives and finally have some power in Washington, the next question becomes: How will they use it? One of the debates that is taking place in the Democratic Caucus has to do with whether the party will investigate or legislate. This is a false choice. The House can do both. The more pertinent question revolves around how they will tackle each responsibility.

If Democrats don’t back away from their oversight responsibility (some may fear seeming like the Republicans who moved forward with charges against Bill Clinton that a majority of Congress did not think rose to the level of high crimes and misdemeanors), then the challenge will be to handle the investigations in a deliberate and methodical fashion. The same way the House Judiciary Committee did in 1974, when it considered President Richard Nixon’s impeachment in a judicious and cautious manner. Similarly, without much hope for passing legislation through a Republican Senate and White House, Democrats need to figure out what issues they will focus public attention on in the lower chamber, so that they can generate debates that better position the party for victory in 2020.

Does the right solidify its hold on the federal courts?

One area that President Trump and the GOP can claim great success in has been with the courts. The administration has been able to move several federal appointees through the federal courts with great speed, and Trump can now rightfully boast about placing two justices — Neil Gorsuch and Brett Kavanaugh — on the Supreme Court. With news that Justice Ruth Bader Ginsburg had cancerous nodules removed from her lungs, 2018 ended with the very real possibility of another conservative justice coming into the picture. Though Democrats can rightly claim that the midterms were a huge success for their party, Republicans did expand their majority in the Senate, which gives the administration huge leverage in its campaign to push the court in a rightward direction.

Will social movements intensify?

The role of grassroots social movements, such as the Parkland students for gun control, #MeToo and Indivisible, has been a remarkable development. We have witnessed the flourishing of grassroots progressive activism at a level that has not been seen for several decades. This past year, average Americans who were frustrated with the administration showed that they could make a huge difference in American politics. Activists shifted the public discourse on issues such as gun control and sexual assault as they mobilized to help candidates win office. Indivisible kept immense pressure on legislators at the local level to stand firm against the President. The kind of energy that all of these citizens brought to the campaign trail could be extremely important to Democrats once again in the presidential election. But maintaining that level of energy and engagement is never easy.

Who are the Democratic front-runners?

With the first Democratic debate set for June 2019, the presidential campaign of 2020 has now officially begun. Over the coming months, the Democratic field will start to take shape. Voters will hear from experienced voices, such as former Vice President Joe Biden, who promises Democrats experience and toughness, as well as promising upstarts like Beto O’Rourke and Kamala Harris, who offer idealism and vision. The early months of the primaries just begin the sorting process. Candidates will start to raise money and to secure the best campaign professionals possible. They will try to develop their name recognition in the media and give voters a taste of their personality. The early shots that each person will take from their competitors will test them in terms of how they will respond to the buzz saw that will be coming from Trump in 2020.

Does the Republican Party finally break?

In the final weeks of the year, President Trump has continued to test his party’s loyalty — with the impromptu announcement of the pullout of troops from Syria and the government shutdown.

Republican legislators could finally start to stand up to the President through legislation, restraining executive power or protecting legitimate oversight. A political breakaway could also come in the form of Republican candidates mounting primary challenges to offer a different outlook for the party. This would give conservative voters who don’t agree with the administration an opportunity to register their disapproval of the President. Or do they continue to remain silent?

Generally, it seems like Republicans are still holding firm. If they started to really break from the President, that would be the most perilous development for a White House that has counted on partisanship from day one.

Will President Trump survive his first term?

Follow CNN Opinion

  • Join us on Twitter and Facebook

    What was once mere speculation has entered into the realm of possibility. With Democrats taking over the House, the President is facing a series of high-profile investigations that deal with very serious charges. While Robert Mueller looks into election interference and possible obstruction of justice, the attorneys general of Maryland and DC want to know whether the President has accepted money from foreign governments, via his hotels, in exchange for access to power. The Southern District of New York is exploring whether Trump Organization executives, other than Michael Cohen, violated campaign finance laws. And in the midst of its legal woes, the Trump Foundation has agreed to dissolve.

    The possibility of impeachment proceedings is now very real. Although Democrats continue to push back when questioned about whether they will attempt to trigger this process, inside of Washington there is clear recognition that the facts on the ground might force their hand regardless of what makes for the best politics.