Bernie Sanders is off to a good start in his run for president. The Democratic candidate has raised $1 million for his campaign in just 24 hours.

The Vermont senator recently announced he’s challenging Hillary Clinton in the Democratic primary for president in 2016. Sanders is an outspoken socialist senator who speaks often of the need for campaign finance reform.

“I don’t believe that the men and women who defended American democracy fought to create a situation where billionaires own the political process,” said Sanders in his press conference announcing his candidacy.”That’s a huge issue.”

While Sanders’ campaign has raised $1.5 million in just a day, the money comes from small donations. The average amount donated was about $43.

“With you’re help we are off to a great start,” tweeted Sanders. “In the last day we had over 100,000 join us, 35,000 donate, and raised more than $1.5 million.”

“This is a remarkable start for Bernie’s campaign,” said Tad Devine, a Sanders adviser. “People across America are yearning for authentic leadership that tells them the truth about what is holding back our nation. Bernie Sanders understands the problems we face.”

While Sanders’ grassroots campaign has some momentum, he admitted it will be difficult to run a campaign without taking money from millionaire donors.

“To run a credible campaign in this day and age, you do need a whole lot of money,” said Sanders. “Whether the magic number is $200 million, or it is $150 million, it is a lot of money, but even with that, you would be enormously outspent by the Koch Brother candidates and the other candidates who will likely spend, in the final analysis, over $1 billion, if not two.”