Follow the 2016 campaign money: Who's got it and who doesn't?

Marco Rubio, Jeb Bush, John Kasich, and Chris Christie, the four Republican candidates in a showdown for their party's traditional supporters, closed last year with roughly as much money in the bank combined as Ted Cruz, the conservative insurgent they hope to topple.

And then there's Donald Trump, a celebrity businessman who has just begun to flex his billion-dollar bank account, lending his campaign $10.8 million from his personal wealth late last year.

The Republican candidates seeking to challenge Trump and Cruz at the top of the field were in varying degrees of financial distress at the end of 2015, fundraising reports filed Sunday night show, with Rubio in the best position to move forward. Together, as the calendar flipped to 2016, the foursome had $21.6 million left in the bank, while Cruz had almost $18.7 million at his disposal.

With voting beginning Monday in Iowa, and continuing next week in New Hampshire, Rubio, Bush, Kasich and Christie were running low on time — as well as money — in their efforts to rise. Should one or more of them continue on after New Hampshire, they'll face a cost-intensive primary calendar that demands travel among some two dozen states and advertising in some of the country's priciest media markets before March 15.

Of the four, Rubio, a Florida senator, led the money chase in the final three months of the year, collecting $14.2 million and ending with $10.4 million in the bank. What's more, he was on the upswing, having more than doubled his fundraising pace from earlier in the year. In total, he collected $39.5 million in 2015.

That's more than Bush's annual total. And the former Florida governor's fundraising fortunes appear to be moving in the opposite direction as Rubio's.

He raised just $7.1 million between Oct. 1 and Dec. 31, about what his haul had been in the preceding fundraising quarter. He closed the year with about $7.6 million in the bank. He had detected a cash crisis in the fall and retrenched his national plan to focus almost exclusively on New Hampshire.

Yet in that state, where voters weigh in Feb. 9, there are two others who also have gone all-in: Kasich, the Ohio governor, and Christie, the New Jersey governor. Those candidates have struggled to gain traction among donors, their fundraising reports show.

Kasich and Christie each raised about $3 million in between Oct. 1 and Dec. 31. Kasich closed out the year with about $2.5 million in cash, and Christie with just over $1 million.

Kasich's allies were eager to portray his financial prospects as improving. Outside groups supporting his bid said they've landed $4 million in checks from six donors in the past few weeks, a period of time not covered by the reports filed Sunday.

Cruz, by contrast, has proved an adept fundraiser. For the year, he raised about $47 million. His most recent report showed 42 percent of that came from contributors giving $200 or less, people who can continue to replenish his treasury. Donors are limited to $2,700 apiece for the primary contest.

That small-donor rate is far better than those of Rubio, Bush, Kasich and Christie.

On the opposite end of giving, the outside groups known as super political action committees also are displaying the effects of a crowded Republican primary. Super PACs can accept unlimited donations but cannot take directions from the candidates they're helping.

Some of these big donors are spreading their largess — splitting much-needed funding among some of the candidates' super PACs.

Chicago investment manager David Herro is a prime example.

Herro gave $50,000 in July to America Leads, the super PAC supporting Christie. But in November, he gave $150,000 to Conservative Solutions PAC, which supports Rubio. His support swung back to Christie in December, though, when he gave Christie's super PAC another $250,000.

Hedge fund manager Seth Klarman also split his money between super PACs for Christie and Rubio. Klarman gave $250,000 to Conservative Solutions PAC in early December. Later that month, he wrote a $100,000 check to America Leads.

New York investment banker Herbert Allen had perhaps the quickest turnaround in support. He gave $50,000 on Dec. 17 to America Leads, then the next day gave $50,000 to New Day for America, the super PAC boosting Kasich.

Julian Robertson, a hedge-fund billionaire, gave $1 million to Bush's super PAC in June and $25,000 to a pro-Kasich group in August. Chris Cline, a coal executive, gave $500,000 to Rubio's Conservative Solutions PAC in September, four months after he gave Bush's Right to Rise $1 million through a limited liability company.

Another multiplayer, Joe Ricketts, the billionaire founder of TD Ameritrade, and his wife, Marlene, have cut checks to groups helping Bush, Christie, Rubio and Cruz — as well as several who are no longer in the race.

Stanley Hubbard, a billionaire Minnesota broadcast executive who doesn't want to see Trump or Cruz at the top of the ticket, said he would spend major money backing any of the four mainstream candidates — if only one would rise to the top.

"If we get someone who really has a chance of doing something, I'm ready," Hubbard told The Associated Press.

There are another six Republicans also vying for the nomination, and most of them saw depleted campaign coffers as of Dec. 31.

Rick Santorum, the former Pennsylvania senator who won the Iowa caucuses in 2012, closed out the year with just $43,000 cash on hand and more than $16,000 in debts to pay. The 2008 GOP Iowa winner, former Arkansas Gov. Mike Huckabee, had less than $134,000 at the end of December — and $50,000 in debts.

THE CLINTON NETWORK

On the flip side, Democrat Hillary Clinton saw a significant jump in outside money late last year. Her campaign is making aggressive use of these groups. A super PAC called Correct the Record works alongside Clinton's campaign, saying it is not running afoul of anti-coordination laws because it isn't spending money on radio or television ads to help her. No other political group is testing that theory.

A second super PAC, Priorities USA, gave Correct the Record $1 million at the end of the year, new fundraising reports show. Priorities, which raised $16.7 million by June 30 saw its coffers balloon to $41.5 million by December.

Its new fundraising report showed 29 donors have given $20 million — or almost 80 percent of its receipts in the last six months of 2015. Billionaire democratic super donor George Soros topped the super PAC's list with a $6 million contribution — a follow-up to $1 million he gave earlier. Media mogul Haim Saban and his wife, Cheryl, gave $3 million, and financier Donald Sussman gave $1.5 million.

Seven others donated $1 million or more, including labor unions such as the International Union of Operating Engineers and the American Federation of Teachers. At the end of the year, the super PAC had $35 million in cash on hand.

Her Democratic competitor Bernie Sanders picked up $33 million compared to her $37 million in official campaign cash from October to December. Sanders continued his dominance with contributors giving $200 or less; those donations made up some 70 percent of his haul.

For Clinton, small donors comprised 15 percent of her fourth-quarter fundraising.

TRUMP LOANS

Trump is in a category all his own. The billionaire businessman loaned his campaign $10.8 million in the last three months of 2015, after relying mostly on contributors during the fall. The new loans represent a return to his long-touted self-funding plan. As he began his campaign last spring, he loaned it $1.8 million.

The leader in many Republican preference polls, Trump has promised to spend whatever it takes to secure the party's nomination, sometimes naming $100 million as a figure. He hasn't had to go deep into his pockets yet, riding a wave of publicity. But he did spend almost $7 million in the final three months of the year, fundraising reports show.

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Associated Press writers Jack Gillum and Jeff Horwitz contributed to this report.

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