The presidential candidates with the bigger Twitter following have won the last three presidential elections, a possible sign that a strong presence on Twitter and other social media outlets is an important factor that can help put candidates over the top.

Only months before the 2016 presidential election, President Trump had 10.2 million followers to Hillary Clinton's 7.7 million, according to a study of Twitter analytics.

When President Obama defeated Mitt Romney in 2012, he had 23.6 million followers to Romney's 1.7 million.

And when Sen. Obama defeated John McCain in 2008, Obama was a relatively new user and had about 118,000 followers, while McCain had a mere 4,942, according to Mashable.

Obama now has a huge Twitter following of 104 million. By comparison, the top account on Twitter belongs to singer Katy Perry, who has 107 million followers.

If Twitter is a real factor in politics, the wave of possible Democratic candidates will have their work cut out for them if they run against Trump. The president now has 56.2 million followers, and none of the other top Democratic tweeters are anywhere close.

As of this week, the top five possible Democratic contenders in 2020 with the highest Twitter reach are:

