Here’s a look at how much the candidates raised and spent in each quarter of 2019. Bernie Sanders Pete Buttigieg Elizabeth Warren Joseph R. Biden Jr. Andrew Yang Amy Klobuchar $50 million 40 30 Raised 20 10 Spent Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Bernie Sanders Pete Buttigieg Elizabeth Warren Joseph R. Biden Jr. Andrew Yang Amy Klobuchar $50 million 30 Raised 10 Spent Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Elizabeth Warren Bernie Sanders Pete Buttigieg $50 million 30 Raised 10 Spent Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Andrew Yang Amy Klobuchar Joseph R. Biden Jr. $50 million 30 10 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Note: Candidates are ordered by the total amount spent in the fourth quarter. Amounts raised are from individual contributions and exclude transfers from previous campaigns. Mr. Biden entered the race after the first quarter. Candidates who are largely or entirely self-funding their campaigns are not shown.

The best-funded Democratic presidential candidates spent prolifically in the final quarter of 2019, pouring millions into advertising and payroll as the first nominating contests approached, according to filings with the Federal Election Commission on Friday. While the candidates competed for support among Democratic voters, President Trump continued stockpiling cash for his re-election bid.

Among the leading candidates in the Democratic primary race, Senator Bernie Sanders of Vermont led the way by spending $50 million in the quarter. That amount is by far the most that he has spent in a single quarter in the 2020 race, and it exceeded what he spent in the fourth quarter of 2015 during his last presidential bid.

[See who led the money race in the first, second and third quarters of 2019.]

Former Mayor Pete Buttigieg of South Bend, Ind., and Senator Elizabeth Warren of Massachusetts each spent about $34 million, and former Vice President Joseph R. Biden Jr. spent $23 million.

Two billionaires who are tapping into their fortunes each spent more than Mr. Sanders, Mr. Buttigieg, Ms. Warren and Mr. Biden put together. Former Mayor Michael R. Bloomberg of New York spent a staggering $188 million, while the former hedge fund manager Tom Steyer spent $154 million.

For the second quarter in a row, Sanders raised the most money from individual donors.

Mr. Sanders’s presidential bid is powered by a huge group of grass-roots donors around the country. He received more than 1.8 million individual donations in the quarter, according to his campaign.

Amount Raised From Individual Contributions (in millions) Note: Fourth-quarter numbers are from Oct. 1 to Dec. 31. Cycle totals include all activity in the 2020 election cycle. Mr. Bloomberg is running a self-funded campaign and is not accepting contributions from donors.

Among top candidates, Biden had the least cash on hand.

The leading candidates are hardly on a level playing field when it comes to the resources they have available to fund their campaigns in the coming weeks.

These figures are now a month out of date, but they show that Mr. Sanders held a significant cash advantage heading into 2020. At the start of January, he had twice as much cash as Mr. Biden.

Cash on Hand (in millions) Note: Figures are as of Dec. 31. Candidates who are largely or entirely self-funding their campaigns are excluded.

As Democrats pour money into Iowa and elsewhere, Trump continues to stockpile cash.

Mr. Trump ended last year with more than twice as much cash on hand as Mr. Sanders, Mr. Buttigieg and Ms. Warren put together. He had more money on hand than President Barack Obama had at the same time during his re-election campaign.

Cash on Hand for Trump and Top Democrats (in millions) Note: Figures are as of Dec. 31.

Five candidates spent more money than they collected in donations.

Candidates who are burning through cash particularly quickly run the risk of running out of money as the primary calendar advances.

Burn Rate Note: The burn rate shown is a candidate’s spending in the fourth quarter relative to individual contributions he or she received. Contribution refunds are excluded from the spending figures. The burn rate is greater than 100 percent if a candidate spent more than he or she raised. Candidates who are largely or entirely self-funding their campaigns are excluded.

Bloomberg is in a class of his own when it comes to spending.

The Bloomberg campaign said it spent $132 million on television advertising, $8.2 million on digital advertising and $3.3 million on polling. It also spent about $650,000 on private plane travel. After Mr. Bloomberg, Mr. Steyer was the biggest spender in the Democratic field.

Amount Spent (in millions) Note: Fourth-quarter numbers are from Oct. 1 to Dec. 31. Totals include all activity in the 2020 election cycle.

Here’s a full look at how the Democratic candidates compare.