After the Democrats reclaimed the House in the 2018 midterm elections, there have been questions as to whether President Donald Trump can finish his term and win re-election in 2020. 

Rep. Jerry Nadler will chair the House Judiciary Committee, while Rep. Adam Schiff will chair the House Intelligence Committee and Rep. Elijah Cummings will chair of the House Oversight and Reform Committee and Rep. Maxine Waters will chair the House Financial Services Committee — four Democrats who could make the coming months very difficult for Trump.

Meanwhile, the special counsel's office appears to be wrapping up its investigation into Russian interference in the 2016 presidential election. Several key Trump advisers have already admitted to crimes or were convicted since 2016.

Democrats may seize on Trump's poor approval ratings to reclaim the White House. The latest Gallup Poll had Trump with just a 39 percent approval rating and a 55 percent disapproval rating — numbers so weak that the normally self-aggrandizing Trump has avoided referencing them on his Twitter account.

Yet there are still reasons to believe Trump can pull off another upset victory.

Mueller Likely Won't Indict A Sitting President

There are a number of charges Trump could face from the Russia probe but many legal experts believe special counsel Robert Mueller will decide to not indict a sitting president, thus clearing a possible path for Trump to remain in office ahead of the 2020 presidential election.

"The indictment or criminal prosecution of a sitting president would unconstitutionally undermine the capacity of the executive branch to perform its constitutionally assigned functions," assistant attorney general Randolph D. Moss wrote in October 2000.

A Republican Senate Will Likely Acquit Trump Of Any Impeachment Charges

Senate Republican can expect to be in a bind about a possible Trump impeachment. Should the House impeach Trump on serious charges, Republican senators who vote no on convicting Trump may have limited justification, which would weaken their support amongst independent voters and even moderate conservatives. Republican senators who vote to impeach would likely face a serious primary challenge to their seat.

Sixty-seven Senate votes are needed to impeach a president and there are 53 Republican senators. That means every Democrat senator would need to vote for impeachment, while 20 Republican senators would need to join them for Trump to be removed from office. 

In other words, it's highly plausible Trump survives impeachment and makes a serious push for re-election.

Meanwhile, should he indeed survive the impeachment vote, there remains the possibility that Trump's approval rating could grow. After Bill Clinton was impeached by the House in 1998, his overall approval rating surged to 73 percent.

And as poor has Trump's current overall approval ratings look, Ronald Reagan had a 41 percent approval rating in December 1982 and Bill Clinton had a 41 percent approval rating in December 1994. Both presidents easily won re-election.

Benefits Of Incumbency

It is rare for an incumbent president to lose a re-election bid and the last two one-termers — Jimmy Carter in 1980 and George H.W. Bush in 1992 — faced a third-party candidate. At the moment, there are no serious third-party candidates that could receive at least 5 percent of the vote and potentially play spoiler. 

The last time a Republican ran as an incumbent was in 2004, when George W. Bush received a stronger showing than in 2000. Prior to that, the previous Republican to win as an incumbent was Ronald Reagan, who won by a landslide in 1984.

Limited Barriers To The GOP Nomination

While former Ohio Gov. John Kasich has flirted with the idea of running for the Republican nomination and former Arizona Sen. Jeff Flake has discussed a possible bid, it's very possible Trump doesn't face a GOP challenger and cruises to the GOP nomination. 

Kasich has stated that he might run as a third-party candidate, while Flake appears to lean more towards not running. 

An unopposed primary is considered crucial for an incumbent's hopes. The past two incumbents to face a primary challenge lost in the general election — Carter was opposed by Ted Kennedy in 1980 and George H.W. Bush went up against Pat Buchanan in 1992.

No Clear Democrat Frontrunner

Will the Democrats nominate the highly experienced Joe Biden or an up-and-coming candidate like Robert "Beto" O'Rourke? Or will the Democrats focus on the economy by nominating Sens. Bernie Sanders or Elizabeth Warren? Could younger Sens. Kamala Harris or Cory Booker make a serious run at the nomination? Do Democrats voters consider another candidate?

A long and contentious Democratic primary might be good news for Trump, who could enter the general election against a bruised and battered opponent with weakened voter enthusiasm.

Trump has stronger odds than any Democratic candidate, according to betting website OddsChecker.

A Strong Approval Rating From Republicans

Through nearly two years in office, Trump still maintains strong approval ratings from Republican voters. According to the last Gallup Poll, Trump has an 89 percent approval rating with Republicans and there is plenty of reason to believe he will remain popular amongst conservatives in red and swing states as he continues his immigration crackdown.

Considering he fell short of Hillary Clinton by 2.9 million votes in 2016, Trump almost certainly knows that appeasing his base is crucial for a 2020 win. 

It helps that Ohio and Florida — two crucial battleground states — both elected Republican governors in 2018. 

More Election Interference?

The Department of Homeland Security and the Director of National Intelligence both concluded that Russia meddled in the 2016 election. Director of National Intelligence Dan Coats noted in December that Russia, along with China and Iran, conducted "influence activities and messaging campaigns" during the 2018 midterm elections.

If 2016 is any indication of what's to come in 2020, continued interference would likely help Trump. Special counsel prosecutors in July said Russian spies attempted to hack Hillary Clinton's email server on the same day Trump urged Russia to find more deleted emails from his opponent. 

James Lamond, managing director of the Moscow Project at the Center for American Progress Action Fund, warned of Russia's continuing influence in U.S. elections in a USA Today opinion article on Nov. 25, 2018. 

"Russia is still targeting our democracy, and there is no reason to believe that it will not interfere in the 2020 presidential election," Lamond noted.