When President-elect Donald Trump won his first term in 2016, he was still a new political figure. His win came as a shock to many, spurring protests and mobilizing opposition across the country. But while his dominance at the highest rungs of American politics remains deeply polarizing and upsetting to many, it's no longer surprising: Trump has been a prominent political figure for nearly a decade now. He and his allies have also had four years to plot a return to office, and they seem ready for a busy start.

Plus, a higher level of intraparty cooperation, paired with his experience as a returning president, could certainly help pave the way for Trump's ambitious plans in the key first 100 days of his second term. Unlike in 2016, when Trump emerged as the seemingly unlikely candidate of a divided GOP, Republicans — along with other Trump allies and national leaders — seem fully prepared to capitalize on his win this time around. "We're seeing a real 180 from his first term that's really kind of stunning," said Brandon Rottinghaus, a political scientist at the University of Houston who helps run the Presidential Greatness Project, a survey of historians published annually. "They've got CEOs and politicians who are more or less catering to his desires even before he takes office. So it's really a big change."

The idea of evaluating presidents based on their first 100 days in office comes from the flurry of activity with which President Franklin D. Roosevelt began his first presidential term in 1933. "It was a series of home runs that FDR hit that let him kind of set the standard for what excellence looked like in an early presidency," Rottinghaus said. And while presidents can recover from a slow start, this early period can often foreshadow what the rest of a president's term may look like, both in terms of their policy priorities and in how well they're able to enact their agendas.

Presidents today need to start especially strong, Rottinghaus said. "The first 100 days are now more consequential than they were even during FDR's time because voters' attention span and their patience is a lot lower than it was. Voters want results faster than ever before, so presidents have to cater to that."

Indeed, Trump began his first term with immediate, high-profile actions, like a ban on travel from predominantly Muslim countries that sparked massive protests and legal challenges. During his first 100 days in office, he signed 33 executive orders, the most since Roosevelt's successor Harry Truman. In turn, President Joe Biden signed 42 executive orders in his first 100 days — largely overturning or reversing actions Trump had taken, including the travel ban — and also worked with the Democratic majority in Congress to pass a major legislative package (known as the American Rescue Plan Act) intended to rein in the health and economic effects of the COVID-19 pandemic.

That trend is likely to continue, as Trump is reportedly planning to issue over 100 executive orders and other actions on his first day in office, including beginning a mass-deportation program, closing the border and reinstating travel bans, rescinding Biden-era electric vehicle incentives, expediting domestic oil drilling, pardoning Jan. 6 defendants, ending protections for gender-affirming care and cutting funding for "woke" schools. Some of those actions may be beyond the scope of the presidency, while others are likely to face challenges in implementation, but making moves to implement them is likely to please some members of his base and continue to fan the flames of the culture wars.

And expectations for Trump's second term seem to be high, driven largely by huge enthusiasm and optimism among Republicans. In fact, while Trump left office historically unpopular, he has enjoyed a recent surge in popularity. That is actually fairly typical for presidents-elect, who tend to enjoy a honeymoon period after they win elections and soon after taking office, so Trump may have a few weeks left in which Americans are prepared to give him the benefit of the doubt.

In a Monmouth University poll from December, 53 percent were optimistic about the policies Trump would pursue in his next term — just a bit higher than the 50 percent who said the same just before he took office in January 2017. Of course, the partisan splits here are also telling. Nearly all Republicans, 97 percent, said they were optimistic about Trump's upcoming policies, while just 10 percent of Democrats are — compared to 90 percent and 18 percent, respectively, in 2017. Meanwhile, the share of independents feeling optimistic ticked up into positive numbers, from 50 percent to 52 percent. Perhaps even more notably, Republicans' strength of enthusiasm has gone up significantly, with 76 percent of Republicans said they were very optimistic, compared to 53 percent in 2017.

When it comes to Trump's policy plans, just over half, 53 percent, of adults surveyed in a Pew Research Center poll from right after the election said they approved of his plans overall. But even more may be hopeful that he'll see success on some of the key policy priorities that propelled him back into office, like addressing the economy and immigration.

Concerns about the economy, especially rising prices and inflation, were undoubtedly among the top reasons voters chose Trump over Vice President Kamala Harris in November. In a Beacon Research/Shaw & Co. Research poll for Fox News from Dec. 6-9, the economy was particularly important to independent voters, a group that likely put Trump over the edge in November: A decisive plurality of 44 percent said it was their top issue, compared to 34 percent of registered voters as a whole. In the same poll, economic issues topped the list of items voters want Trump to focus on, as 60 percent of voters said it was "extremely important" that Trump focus on lowering the price of food and gas and 47 percent said the same about cutting individual taxes.

It's no surprise then that Trump's promised to tackle economic issues as soon as he takes office. His promise to "drill, drill, drill" — something he famously said he would be a "dictator" to implement on "day one" of his presidency, is part of his strategy to bring down gas prices. He's also expected to take action on tariffs and tax cuts, policies that he's argued will increase domestic jobs and lower costs for individuals — though many economists have expressed skepticism about whether this would actually be the case.

Americans and even Trump himself have both seemed to acknowledge that reducing everyday costs is a difficult task. While 60 percent of Americans in a December Gallup poll said they think Trump will be able to reduce unemployment and 58 percent thought he will "improve the economy," under half (47 percent) thought he would reduce grocery prices. "I'd like to bring them down. It's hard to bring things down once they're up. You know, it's very hard," Trump said in a December interview with Time magazine.

On this score and many others, voters' expectations for what they want a president to do — including fulfilling promises made on the campaign trail — may not be realistic. "There's a concept that political scientists talk about called the expectations gap, and that's the difference between what presidents … can accomplish versus what we expect them to accomplish, and it's often quite unfair to presidents to labor under these expectations," said Justin Vaughn, a political scientist at Coastal Carolina University who coauthors the Presidential Greatness Project with Rottinghaus. "I'm not totally sympathetic to presidents in this situation, though, because they also encourage these expectations. They spend a year or two on the campaign trail promising everything under the moon to voters in exchange for their vote."

While presidents don't have direct control over the economy, they have broader authority over immigration policy. Painting immigration as an existential threat to the country has long been a key part of Trump's brand, and taking decisive action on immigration off the bat will be particularly important in appealing to his base. In the Fox News poll, immigration edged out the economy as the top issue among Republican voters. And in the Gallup poll, immigration was the issue on which Americans had the highest expectations for Trump: 68 percent said they thought Trump would be able to control illegal immigration.

Alex Hinton, an anthropologist at Rutgers University–Newark who has studied the Make America Great Again movement, said that while voters ranked the economy as important, the issue of immigration, alongside other "culture war" issues, were the ones that inspired the most passion among Trump supporters at the rallies he witnessed. "They want to have what they perceive as this massive immigration problem resolved," Hinton said. "And so we will have, I think, spectacular raids that take place, and that also will play to appeal to a lot of the voters. So I think at least initially, there'll be some stuff done that will satisfy many, many of the voters."

Indeed, Trump seems prepared to take highly visible actions on immigration as soon as he takes office. "When I win on Nov. 5, the migrant invasion ends and the restoration of our country begins," Trump said at an October campaign rally. And sure enough, heading into his second term, his promises to reinstate travel bans, end birthright citizenship and begin mass deportations on day one would be a signal to his base that he will attempt to make good on those promises.

But there are other actions Trump has promised to take on day one that may prove more divisive, and could cost him some public support. For one, many Americans remain concerned about Trump's threats to democracy and institutional norms. Trump repeatedly threatened on the campaign trail to seek retribution against his political enemies. While 71 percent of Republicans in the Monmouth poll said they thought Trump was exaggerating, 48 percent of independents and 77 percent of Democrats took him seriously. And voters across the board said it would bother them at least some if he did so: 57 percent of Republicans, 76 percent of independents and 89 percent of Democrats.

Trump's immediate plans reportedly include firing the team that worked on the federal prosecutions against him under special counsel Jack Smith (who has already resigned), and pardoning defendants who participated in the Jan. 6 Capitol insurrection. Beyond this, Trump has also promised — or already begun enacting — efforts to remake the federal workforce, including by shrinking the number of civil service jobs and establishing a Department of Government Efficiency intended to slash government spending, led by businessmen Elon Musk and Vivek Ramaswamy. And voters as a whole have expressed serious concern over plans by Trump and his allies to expand the power of the executive branch, including in ways that would allow him to act without relying on Congress.

Perhaps because of that, most Americans aren't very hopeful that Trump will be a uniter rather than a divider as president. Only a third of Americans thought Trump would be able to "heal political divisions in this country" in his second term, according to the Gallup poll.

Of course, the first 100 days of a presidency are only a small portion of a presidential term. To take Biden as a recent example, Rottinghaus and Vaughn emphasized that while historians in their most recent survey last February gave him fairly high marks as a president (he ranked 14th out of 45 presidents), the events of last year, with Biden dropping out of the presidential race and Trump overcoming a previous defeat to win the presidency a second time, will likely lead historians to reassess how they evaluate Biden's one-term presidency.

"I think unfortunately for President Biden, [his legacy] is going to be the guy who spent his entire adult life trying to become president, eventually did under the promise that he would be a bridge to a new generation, then changed his mind, stubbornly refused to step aside, and ultimately ended up being the reason that Donald Trump became president again," Vaughn said.

For his part, with his now-lengthy career at the top of American politics, Trump will undoubtedly prove to have a lasting impact on the country. And with Republicans in both chambers of Congress united behind him, the first 100 days will likely offer only a small hint at what Trump's second term will look like.