Booker announced the figure in an email to supporters. The sum puts him near the back of the pack in fundraising with roughly 10 months left before the start of Democratic primary voting. Of those candidates that have announced their figures, only entrepreneur Andrew Yang announced raising less than Booker.
Former Texas Rep. Beto O'Rourke raised $6.1 million during his first 24 hours of presidential campaigning beginning March 14, edging Vermont Sen. Bernie Sanders' $5.9 million over the same period to top the Democratic field.
Booker said Sunday he feels "incredible" about the fundraising haul. "Money is important, but it is definitely not going to be the barometer with which people make their decisions over who's going to be the next president of the United States," Booker said. "And I'm happy that we have the resources we need to be in this race."
On the policy front, Booker on Sunday promoted a program known as baby bonds. It calls for newborns to get a savings account. The government would contribute up to $2,000 to the account annually until the child is 18. The amount would depend on their parents' income.
Booker's campaign says it's expected that one in 10 kids in New Hampshire would receive the full $2,000 contribution annually. He said the plan would let kids use the fund to get training, to go to college, to start a business or to buy a home. Booker said the idea is to "create a fair playing field where everybody has a stake in this economy."
Elsewhere in campaigning Sunday: PETE BUTTIGIEG The mayor of South Bend, Indiana, defended his experience ahead of an expected run for president, saying he isn't someone who has "been marinating in Washington" for a long time.
Asked on NBC's "Meet the Press" about his qualifications, he said he would "stack up my experience against anybody," though he acknowledged "it's not as traditional." The Democratic field is full of senators and members of the House.
Buttigieg said "being a mayor of a city of any size means that you have to deal with the kinds of issues that really hit Americans." Buttigieg would not confirm that he plans to announce his candidacy at an event next Sunday in South Bend but said "the kind of thing we're going to announce is the kind of thing you only get to announce once."
Buttigieg was campaigning in New Hampshire this weekend.
Democratic presidential hopeful Bernie Sanders said Sunday he favors a comprehensive immigration overhaul.
But when asked at an Oskaloosa, Iowa, town hall why he supported open borders, Sanders replied, "I'm afraid you may be getting your information wrong. I think what we need is comprehensive immigration reform."
The Vermont senator continued: "Oh my god, there's a lot of poverty in this world, and you're going to have people from all over the world. And I don't think that's something that we can do at this point. Can't do it," he said of open borders.
Sanders came under fire during the 2016 campaign for opposing a comprehensive immigration overhaul bill in 2007 over concerns it would depress wages and hurt U.S. workers. The stance that aligned him closely with a number of unions at the time. He supports a pathway to citizenship for children brought into the U.S. illegally by the parents, and in 2013 supported the comprehensive immigration legislation backed by the bipartisan Gang of Eight senators, which ultimately failed in the House.
He has not yet released an immigration policy outline for his 2020 campaign.
Sanders made his comments during a two-day swing through a handful of rural Iowa towns. During the Oskaloosa event, he took six questions from the crowd, on issues ranging from the feasibility of his economic policies to whether he'd unite the Democrats after the primary.
The Colorado senator was in New Hampshire, days after he made his prostate cancer diagnosis public. Bennet said earlier this weekend that he wasn't dwelling on the diagnosis and spoke to voters about health care and partisan divides in Washington.
He also told CNN's "State of the Union" that he hopes to announce a run for president "as soon as I can," depending on his health.
"I have got to go through a procedure at the beginning of the upcoming recess," Bennet said. "That starts later this week. And then it's going to be a couple of weeks for recovery. But I would like to get on with this."
He added that he's "looking forward to running in 2020."
"This obviously was unexpected," Bennet said. "But we caught it early. It's something that I think we're going to be able to treat. And I don't think it should keep me off the trail."