By Brian Schwartz, Tucker Higgins, and Carmin Chappell, CNBC

Sen. Elizabeth Warren, D-Mass., announced Monday that she had formally launched an exploratory committee for a 2020 presidential bid.

The former Harvard professor made the announcement in a video emailed to supporters. In the four-minute video, Warren promoted a message of economic fairness, while targeting corruption and racial inequity.

"Our government is supposed to work for all of us, but instead, it has become a tool for the wealthy and well-connected," Warren said in the video.

She said corruption is "poisoning our democracy," warned that "America's middle class is under attack" and cited the obstacles facing minority groups.

"Families of color face a path that is steeper and rockier, a path made even harder by the impact of generations of discrimination," she said.

Warren is already planning to travel to the early caucus and primary states, including Iowa, in the coming weeks, according to a source with direct knowledge of the matter.

Read the full story on the CNBC website.