Donald Trump
Trump filed the paperwork to run in 2020 just hours after he was inaugurated in 2016.
No Republicans have announced their intention to run against him, though there has been speculation of an anti-Trump GOP insurgent campaign.
Republican Senate Majority Leader Mitch McConnell said in October that he believes it would be a "waste of time" for any Republicans to try.
Bernie Sanders
The 2016 Democratic runner-up is expected to run in 2020, though he has not confirmed his intentions.
In August, he won the Democratic nomination in Vermont's Senate primary, but he turned it down, further fueling speculation.
Amy Klobuchar
Democrat Senator Amy Klobuchar's name has been floated for the party's presidential nomination after her landslide win in Minnesota in the midterms.
Political commentators said she could be a serious contender after she performed well in rural counties.
Kamala Harris
The California senator — the second black woman ever elected to the US Senate — was first elected in 2016 as a tough opponent of the Trump administration.
She played a leading role in the Democrats' midterm efforts, gathering resources for the party.
Kirsten Gillibrand
New York Senator Kirsten Gillibrand, who was re-elected in the midterms, told Stephen Colbert in November that she would give running in 2020 "a long, hard thought of consideration."
"I’ve seen the hatred and the division that President Trump has put out into our country, and it has called me to fight as hard as I possibly can to restore the moral compass of this country," she said.
Hillary Clinton
A former senior aide to Hillary Clinton said in October that there was a "not zero" chance she could decide to run for president again.
Michael Avenatti
Attorney Michael Avenatti, lawyer for adult film star Stormy Daniels and a vocal Trump critic, said in October that he is "seriously considering" challenging Trump in 2020.
Michael Bloomberg
The billionaire former New York mayor is exploring a run for the presidency.
He was first elected mayor as a Republican, then later re-elected as an independent, but financially supported Democrats during the midterms and officially registered as a Democrat in October.
Cory Booker
The New Jersey senator is regularly mentioned as a potential candidate and gained popularity and name-recognition among many liberals for his opposition to Supreme Court nominee Brett Kavanaugh.
Booker has placed staff on the ground in Iowa, the Guardian reported.
A CNN poll of potential 2020 Democratic presidential nominees in October ranked him fifth.
Beto O'Rourke
O'Rourke was the Democratic US Senate candidate in Texas, and while he ultimately lost to Ted Cruz he was by far the best-funded and most competitive Democrat to run statewide in Texas in years and brought Democrats closer than expected to flipping the red state.
His campaign made him a national figure, frequently compared to former presidents John F. Kennedy and Barack Obama.
Joe Biden
The former vice president has not publicly decided if he will run in 2020, and said he won't think about it until January, but he is the early leader for the 2020 Democratic Party nomination, according to Reuters poll published in November.
Elizabeth Warren
The Massachusetts Senator is expected to run in 2020, though she has not said so publicly. Trump reportedly thinks Warren will be his 2020 opponent.
Warren said in September that she would consider running "after the midterms."
Eric Swalwell
The 37-year-old California congressman is "definitely running," a source told Politico in November.
However, Swalwell told The Hill he has nothing to announce in that regard "yet."
John Delaney
The former San Antonio mayor and secretary of Housing and Urban Development for President Obama told Rolling Stone in October that he is "likely" to challenge Trump in 2020.
Delaney campaigned for Democrats across the country in the midterms.
Julian Castro
The former San Antonio mayor and secretary of Housing and Urban Development for President Obama told Rolling Stone in October that he is "likely" to challenge Trump in 2020.
Castro campaigned for Democrats across the country in the midterms.
Tulsi Gabbard
The Hawaii congresswoman is considering running in 2020, a source with direct knowledge of her deliberations told Politico.
Tim Kaine
Kaine, Hillary Clinton's vice presidential pick in 2016, is considered a 2020 prospect. He was re-elected as Virginia senator in the midterms.
Steve Bullock
The Montana governor gave a speech in August that touted his ability to win in Trump country, sparking speculation of a potential 2020 run.
Terry McAuliffe
The former Virginia governor told reporters in September that he hadn't ruled out a potential White House bid, and he campaigned on behalf of Democrats during the midterms.
A new super PAC aimed at encouraging him to run was launched in the same month.
Eric Garcetti
The mayor of Los Angeles hinted at a run in 2017, and said that he was "thinking hard" about a potential run in October.
John Hickenlooper
The Colorado governor told Politico he is considering a 2020 run, adding that he has seen "an interest … a genuine interest in terms of what we’ve done in Colorado."
Tim Ryan
The Ohio congressman has been telling political consultants and operatives that he intends to run, sources told The Intercept in June.
Jay Inslee
The Washington state governor said in October that at he is "not ruling out" a presidential run.
Deval Patrick
Former Massachusetts Gov. Deval Patrick has said that a 2020 run is on his "radar screen," and he launched a PAC in August. However, Patrick said in September that he wasn't "sure" there is a "place" for him in what seems certain to be a crowded race.
Sherrod Brown
The Ohio senator said in early November, "I don't like the idea of running for president."
But Brown's midterm reelection victory speech suggests 2020 is on his mind, after he boasted of winning in a state that "pundits say is just too hard for a progressive Democrat."
"We celebrate the worker. And that is the blueprint for America in 2020," Brown said.
