WASHINGTON (AP) — Vermont Sen. Bernie Sanders says he has raised $1.5 million online in the first day since launching his Democratic presidential campaign.

The independent senator says he has received contributions from 35,000 donors, and more than 100,000 people have signed up on his website.

Sanders filed papers to run for president on Thursday, becoming the first major challenger to enter the race against Hillary Rodham Clinton. She opened her campaign earlier this month.

Clinton is heavily favored but Sanders has positioned himself as a liberal who intends to promote economic and environmental issues and oppose contentious trade legislation.

Sanders plans to make stops Saturday in New Hampshire, the home of the nation's first presidential primary. It will be his 10th trip to New Hampshire in the past year.