Over 28,000 people showed up to hear presidential candidate Sen. Bernie Sanders, I-Vt., speak in Portland, Oregon, on Sunday, setting the record for the largest crowd to attend one of his campaign events, and in the 2016 presidential race thus far.

More than 19,000 people filled an NBA arena while around 9,000 others stood outside hoping to get in, said Michael Lewellen, vice president of corporate communications for the arena, reports CNN. Altogether, Lewellen said a total of 28,000 people tried to attend the event, which was live-streamed on his campaign's web site.

"Whoa!" Sanders said as he took stage at the Moda Center, where the NBA's Portland Trail Blazers play. "This is an unbelievable turnout."

During his speech, Sanders condemned the political influence of the "billionaire class" and promised to fight for working class Americans by increasing minimum wage increase, expanding Social Security benefits and offering free college education.

In comparison, Democratic presidential frontrunner Hillary Clinton's largest crowd topped out at around 5,500 people at her presidential kickoff event in New York.

On Saturday, the self-described democratic socialist drew about 15,000 people to an arena in Seattle at another political event, reports the Washington Post. However, protesters aligned with the Black Lives Matter movement hijacked his podium when he was about to speak. As a result, he patiently waited on the side, and then left without addressing the crowd.

Rather than just pandering to left-leaning supporters, Sanders plans to address an audience at a conservative Christian college in September. The Vermont senator released a statement announcing that he will be a speaker at the Sept. 14 convocation at Liberty University, a Virginia-based evangelical school with traditionally strong political ties to the Republican Party.

"Liberty University was kind enough to invite me to address a convocation and I decided to accept," reads the statement released by the Sanders' campaign last week. "It goes without saying that my views on many issues -- women's rights, gay rights, education and many other issues -- are very different from the opinions of some in the Liberty University community."