Democratic 2020 U.S. presidential candidate Senator Bernie Sanders marches with student supporters to an on-campus polling place for early voting at Winston-Salem State University in Winston-Salem, North Carolina, February 27, 2020.

Bernie Sanders' campaign says it raised $46.5 million in February, a staggering influx that leaves the Vermont senator flush with cash as he tries to build his presidential primary delegate lead.

The Sanders campaign also announced Sunday that it will buy TV ads in nine states that hold primaries later this month. They are Arizona, Florida, Idaho, Illinois, Michigan, Mississippi, Missouri, Ohio and Washington.

The February haul, which nearly doubles the still impressive $25 million the campaign raised in January, came as Sanders rode victories or strong showings in the first 2020 Democratic presidential nominating contests to an early national delegate lead. Sanders has trounced his Democratic rivals in contributions from individual donors: $46.5 million is more than all of his non-billionaire rivals combined raised in January.

But Sanders was not the only candidate to see a flood of cash in February. Sen. Elizabeth Warren, D-Mass., raised about $29 million during the month, her campaign said Sunday.

The Sanders campaign said it is already running TV ads in 12 of the 14 states voting this week on Super Tuesday. Strong performances in California and Texas, which award the most delegates on that day, will be critical for Sanders' push to secure the majority of delegates needed to win the nomination.

Projected delegates so far from former Vice President Joe Biden's decisive win in South Carolina's primary on Saturday bring him to 51, just six shy of Sanders' 57, according to NBC News. Biden bundlers saw increased donor interest in backing his campaign after the result.

On Sunday morning, Biden told NBC News that his campaign raised $5 million in the last 24 hours.

Sanders would have a decisive cash advantage over his rivals if not for billionaire former New York Mayor Mike Bloomberg, who has dipped into his personal wealth to spend more than $400 million (and counting) on his presidential campaign.

The Sanders campaign says it has now received 8.7 million donations since February 2019, more than the senator's 2016 presidential campaign got.

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