(CNN) Cory Booker raised more than $5 million during the first quarter of his presidential campaign, the New Jersey senator announced in an email to supporters Sunday.

"I feel incredible," Booker said Sunday of his fundraising numbers during a stop in New Hampshire. "We set goals for ourselves and we surpassed our own goals, we're seeing incredible energy and enthusiasm everywhere we go in this campaign."

Booker also touted a total of $6.1 million cash on hand, a sum some of his rivals, like Buttigieg and Harris, did not disclose. The figure suggests a relatively low burn rate for Booker; it also indicates that he transferred some money from his Senate account. But Booker's email reported that there remains more money left in that bucket available to be tapped at a later date.

The numbers overall suggest that, while Booker's campaign should have no problem keeping the lights on, he is not among the fundraising powerhouses in this race, particularly in grassroots fundraising — a useful marker of enthusiasm at this stage.

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