Washington(CNN) Sens. Elizabeth Warren, Kirsten Gillibrand and Bernie Sanders enter 2019 with a significant initial cash advantage over other Democrats running or thinking about running for president in 2020, according to new reports filed with the Federal Election Commission.

Warren reported having over $11 million in the account for her US Senate campaign committee at the end of 2018, per her year-end Federal Election Commission report. Gillibrand reported over $10.3 million in cash on hand for her Senate campaign committee, the second highest total among those 2020 contenders filing reports. And Sanders, whose grassroots fundraising strength helped power his 2016 presidential campaign, reported having just over $9.09 million in the bank.

No other contender filing a year-end report had more than $5 million in cash on hand.

That's money that can be transferred to a presidential campaign. And the same goes for any other potential candidates who currently hold federal office and have funds available in their principal campaign committees, giving them a head start over some of their potential opponents. In a crowded primary field, in a presidential race expected to smash spending records, an initial cash edge can give candidates critical resources to get their message out early.

Sen. Kamala Harris flashed robust fundraising potential when she announced that she had raised more than $1.5 million in the 24 hours following her presidential campaign announcement. Separately, the California Democrat reported having just over $1.3 million in the account for her Senate campaign committee at the end of the year.

Warren's presidential exploratory committee -- formed just before the year-end reporting deadline -- didn't report any contributions or cash on hand, but an analysis of contributions detailed in ActBlue's report suggests Warren raised $299,000 on the platform on the day of her announcement, though that total doesn't capture any funds Warren may have raised outside of ActBlue. Warren, Harris, and any other White House aspirants who announce before March, will file a more complete accounting of their presidential fundraising activities at the end of the first quarter.

Former Housing and Urban Development Secretary Julian Castro, who announced his White House bid in mid-December, had over two weeks in the year-end period to raise funds, and his presidential committee reported raising just over $220,000 and has about $200,000 in cash on hand.

Other senators who filed year-end reports include Sen. Cory Booker, who reported $4.1 million in cash on hand, the fourth-highest total; Sen. Amy Klobuchar with $3.9 million; and Sen. Sherrod Brown with nearly $1.4 million.

Rep. Tulsi Gabbard, who is running for president, reported having over $2 million in cash on hand from her US House campaign committee

Beto O'Rourke smashed fundraising records amid his losing Texas Senate campaign in 2018 and launched himself into the presidential conversation, but he spent nearly all of the $80 million he raised in the midterms and reported having just $286,531 in cash on hand.

Rep. Eric Swalwell, who said this week he is "close" to announcing a decision on 2020, reported $1.67 million in cash on hand.

John Delaney, a former House member who has been campaigning for president since July 2017, reported $268,248 in cash on hand for his presidential campaign, and reported loaning his campaign $1 million in the last quarter of 2018.

Another key gauge of a candidate's strength is their small dollar fundraising support -- how much money they raised from contributions under $200. Warren (92.7%), Gillibrand (81.66%), Harris (73.3%), Brown (78.9%) and Gabbard (93.4%) all benefited from high small-dollar support, calculated as the percentage of individual contributions they received that came from those small-dollar donors.

The year-end reports also shed light on the spending activity of 2020 contenders in the period immediately preceding some of their presidential announcements.

Warren, just weeks from her announcement, spent the most on transfers to state party committees, staff salary, and internet advertising, while Harris directed the vast majority of her spending to web advertising. Gillibrand spent the most on staff salary and communications consulting, according to her report, while Booker split is spending mostly on a mix of staff-related expenditures, advertising and fundraising consulting service.