Joe Biden raised $5.3 million in October in a surge of small-dollar online contributions that rolled in after President Donald Trump launched unfounded attacks against the former vice president over his son’s Ukrainian dealings.

The swell of cash was raised from through 182,000 donations, with an average amount of about $28, according to figures provided to The Associated Press by Biden’s presidential campaign. It comes after his internet fundraising operation stumbled over the summer, leading critics to suggest he lacked grassroots support.

“All of the Trump attacks have started to catalyze. More people understand what is at stake,” deputy campaign manager Pete Kavanaugh said in an interview. “People out there are seeing Joe Biden getting attacked day after day. They understand he needs to fight back.”