(CNN) Sen. Kamala Harris' campaign says she raised $1.5 million online in just 24 hours after declaring she would run for president in 2020.

The campaign released snapshots of fundraising data that reflected an initial surge of financial support for the California Democrat.

The numbers could not immediately be independently confirmed by CNN, and a more complete picture will be available when the campaign files its first Federal Election Commission report after the first quarter of the year.

The campaign says the $1.5 million came from over 38,000 individual donors, from all 50 states, with an average contribution of $37, and $1 million was raised in just the first 12 hours after the announcement. The campaign also said it had broken the single-day, single-candidate record for sales by its merchandise vendor.

Harris -- the first major 2020 candidate to release fundraising data -- posted numbers that are comparable to those of Sen. Bernie Sanders during his 2016 presidential campaign. The Vermont independent made headlines when he announced that he had raised $1.5 million from 35,000 contributors for his (then) long-shot bid in the 24 hours following his declaration, an early indicator of the robust small-dollar fundraising support that would power his Democratic primary challenge.

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