Robert F. Kennedy Jr., a controversial member of the storied Kennedy family who is known for his anti-vaccine views, has filed to run for president, according to a statement of candidacy submitted to the Federal Election Commission.

Kennedy, the nephew of the late President John F. Kennedy and the son of former attorney general and Sen. Robert Kennedy, filed paperwork with the FEC on Wednesday, saying he was running as a Democrat.

He becomes the second Democrat to launch a long-shot bid ahead of President Joe Biden's expected announcement of another presidential run. Self-help guru Marianne Williamson also is running.

Kennedy, 69, parlayed his famous last name into years of advocacy as an environmental lawyer and best-selling author. He has become more known in recent years as one of the leading anti-vaccine advocates in the country, peddling false claims linking vaccines to autism. In 2019, Kennedy's family publicly criticized him over his anti-vaccine activism. He gained even more notoriety during the pandemic as one of the nation's most prolific spreaders of disinformation about coronavirus vaccines. He apologized in January 2022 for invoking Anne Frank to imply Jews had more freedoms during the Holocaust than Americans who chose not to get vaccinated have today.

Kennedy teased his candidacy in March, writing on Twitter, "Help me decide whether to run for President," and, "If it looks like I can raise the money and mobilize enough people to win, I'll jump in the race."

Biden, 80, is expected to announce his plans to run for another term this spring.