Former President Donald Trump speaks at a campaign event at the South Carolina Statehouse on January 28, 2023, in Columbia, South Carolina.
CNN  — 

Former President Donald Trump’s political operation brought in $9.5 million in the roughly six weeks after he announced his latest White House bid, according to a source familiar with the fundraising numbers.

The haul is smaller than the nearly $11.8 million raised by Trump entities in the six weeks before the Republican’s November 15 campaign announcement, underscoring the challenges Trump faces as he attempts a political comeback.

In an effort to boost donations, Trump’s team has hired marketing agency Campaign Inbox to bolster its digital fundraising operation, the source confirmed to CNN.

Trump’s team said the former president, who is the first major declared candidate of the 2024 presidential race, would have the funds to compete.

Campaign spokesman Steven Cheung said on Tuesday that, in all, the political operation raised a total of $21.3 million in the final quarter of last year. He said that proves the former president is “an unstoppable force that continues to dominate politics.”

Cheung said Trump would carry out “an aggressive and fully-funded campaign.”

NBC first reported Trump’s year-end campaign figures.

New reports filed Tuesday night with the Federal Election Commission show that Trump’s main campaign committee started the year with a little more than $3 million in available cash.

But his political operation has many arms and a mountain of cash.

In all, five Trump-aligned committees reported having a total cash stockpile of more than $81 million.

Two-thirds of that sum – or more than $54 million – sits in the coffers of MAGA Inc., a super PAC established last year and run by former Trump campaign aide Taylor Budowich that must operate independently of the campaign. It can spend heavily, however, to boost the former president and strike out at his rivals.

A potential 2024 candidate who has faced early attacks from Trump, Florida Gov. Ron DeSantis, has also built a substantial war chest.

DeSantis’ political operation – split between two Florida-based committees – had more than $75 million remaining in its coffers after the 2022 midterm elections, according to the most recent filings with the state. The Florida Republican shattered fundraising records on his way to winning a second term last year, raising more than $163 million for his state political committee, Friends of Ron DeSantis, and another $50 million through his campaign.

DeSantis has yet to announce a White House bid, but CNN has previously reported that DeSantis’ political operation was exploring how to shift money from a state political committee into a federal committee that could potentially support a presidential campaign.

In Trump’s first major campaign swing – weekend visits to the early voting states of New Hampshire and South Carolina – he took aim at DeSantis, describing him as “disloyal” for weighing a presidential run and criticizing the governor’s pandemic response.

DeSantis responded by touting the margin of his reelection victory last year. He won by 1.5 million votes, the largest margin in state history.

Other potential 2024 contenders also have more modest sources of funds that they could tap for campaigns-in-waiting, including several former Trump administration officials. Former Vice President Mike Pence’s PAC, Great America Committee, reported just $80,000 in cash on hand at the end of 2022.

And former UN Ambassador Nikki Haley, who is expected to announce a presidential bid on February 15, has about $2 million in cash on hand in her PAC, Stand for America.

South Carolina Sen. Tim Scott, who is set to travel to Iowa in February, has amassed an impressive stockpile of over $21 million, according to his latest FEC report, which he could put toward a White House bid.

This story has been updated with additional information.

CNN’s Steve Contorno and Kit Maher contributed to this story.