Hillary Clinton officially has a challenger for the Democratic nomination: Sen. Bernie Sanders is running for president.
Sanders, who plans to formally announce his 2016 campaign on Thursday, told the Associated Press and USA Today that he's running. "I am running for president," he told the AP.
"I've been traveling around the country for the last year trying to ascertain whether there really is grass-roots support in terms of people standing up and being prepared to take on the billionaire class," Sanders elaborated to USA Today. "I believe that there is."
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He will formally announce the bid Thursday in a statement and press conference. The press conference had been scheduled for a room in the U.S. Capitol Building, but will likely be moved to avoid the appearance of using official congressional resources for political goals, an aide told msnbc, although other presidential candidates have announced their bids on the Capitol campus.
The 73-year-old independent Vermont senator plans to run as a Democrat, making him the second candidate from the party to officially declare his run. He'll face a steep challenge against the first candidate, former Secretary of State Hillary Clinton, who holds an "unprecedented" early lead, and may push her to left on some issues.