Nearly all 2012 Republican candidates - Ron Paul, Newt Gingrich, Mitt Romney and others - claim they are fiscal conservatives. That is, they promise to cut the U.S. national debt through reduced government spending.

Being perceived as a fiscal conservative is crucial to winning the Republican nomination, according to multiple polls. Indeed, Americans have become increasingly concerned about the ballooning national debt, which recently exceeded 100 percent of the GDP.

But which candidate actually walks the walk on fiscal responsibility?

Below is a summary of the campaign finances of Paul, Gingrich, Romney and President Barack Obama from OpenSecrets.org (as of Sept. 30, 2011).

Ron Paul

Total Raised: $12,623,422

Total Spent: $8,948,654

Cash on Hand: $3,674,768

Debts: $0

Newt Gingrich

Total Raised: $2,897,954

Total Spent: $2,544,537

Cash on Hand: $353,417

Debts: $1,192,866

Mitt Romney

Total Raised: $32,212,389

Total Spent: $17,559,845

Cash on Hand: $14,656,966

Debts: $0

Barack Obama

Total Raised: $86,215,580

Total Spent: $27,115,268

Cash on Hand: $61,403,711

Debts: $1,709,300

Comments

Paul is spending most of the money he raised, saving some of it and accruing no debt. Romney has saved 45 percent of the money he raised so far. Obama, strangely, has $1.7 million in debt even though he has more than enough cash to pay it back.

(For Romney and Obama, their records also speak for themselves; Romney balanced the budget of Massachusetts by raising fees and cutting spending while Obama presided over a $4 trillion expansion of the national debt.)

Gingrich is the big debtor in this group.

As of Sept. 30, he had $1.2 million in debt even though he raised only $2.9 million. He had just $350,000 in cash.

When Gingrich finally decided to tackle his enormous debt, one debt he paid back more quickly than many others is the $42,000 his campaign owed to him personally for using his mailing list, according to the Washington Post.

(Watchdog group Citizens for Responsibility and Ethics in Washington (CREW) has filed a complaint with the Federal Election Commission (FEC) to request an investigation of the $42,000 payment).

So why does the former House Speaker have so much debt?

It was mainly due to luxury jets and other pricey expenses racked up in the early weeks of his campaign, wrote the Washington Post. His biggest debt ($451,946) is towards Moby Dick Airways, a private jet company.

Gingrich's precarious financial situation meant he is behind in his ability to match opponents' spending in early-voting states, where he has just started to pay for advertising and is scrambling to catch up on staffing, wrote the Washington Post.

Sounds like a personal lesson in fiscal discipline.