A few governors with presidential ambitions got less-than-stellar grades from the nation's leading libertarian organization.

The CATO Institute’s annual “Fiscal Report Card on America’s Governors” graded the nation’s governors on their tax and spending policies — and just four top state executives managed to snag A's.

New Jersey Gov. Chris Christie campaigns with Wisconsin Gov. Scott Walker at Empire Bucket in Hudson, Wis., Sept. 29, 2014. (AP Photo/Ann Heisenfelt)

The four who got A's were all Republicans, while the eight who received F's were Democrats. But the high- and low-scorers weren't purely split down party lines: a few Republicans state leaders got C's and D's, while a couple of Democratic chief executives came away with B's.

CATO said it used statistical data to "grade the governors on their taxing and spending records — governors who have cut taxes and spending the most receive the highest grades, while those who have increased taxes and spending the most receive the lowest grades."

The governors were graded on a curve; the highest-scoring was North Carolina’s Pat McCrory, who got a 78 and got an A. The lowest-scoring was California’s Jerry Brown at 19, an F. Brown is up for re-election this year and is expected to win easily.

Indiana Gov. Mike Pence was the only potential 2016 presidential contender to get an A.

Most other Republican governors that seem likely to enter the 2016 presidential race received B's, including New Jersey’s Chris Christie, Wisconsin’s Scott Walker, Louisiana’s Bobby Jindal and Rick Perry of Texas. Walker is also facing a competitive re-election battle this year.

New York Gov. Andrew Cuomo, a potential Democratic candidate for the White House, also got a B; Cuomo is expected to be re-elected easily in November.

Two other likely presidential contenders got D's: Republican John Kasich of Ohio and Democrat Martin O’Malley of Maryland. Kasich appears headed for re-election in November.

Florida Gov. Rick Scott -- a Republican in one of the most-watched races this year, only earned a D from the CATO report. Meanwhile, two Democrats in closely watched races this year – Illinois Gov. Pat Quinn and Colorado Gov. John Hickenlooper – got F's.

Assessing the challenges states face, the report said: “Many retirement plans for state workers have high levels of unfunded liabilities, and the Medicaid expansion under the 2010 Affordable Care Act will increase stress on state budgets. At the same time, global economic competition is making it imperative that states improve their investment climates, particularly by cutting tax rates on businesses and entrepreneurs.”

The report skipped Virginia, because Democrat Terry McAuliffe took office just this year, and Alaska, which the report said has “peculiarities in that state’s budget.”

Below is a partial list of governors and their grades:

Alabama

Governor Robert Bentley

Grade B

Score 62

Arizona

Governor Jan Brewer

Grade C

Score 52

Arkansas

Governor Mike Beebe

Grade D

Score 49

California

Governor Edmund G. Brown

Grade F

Score 19

Colorado

Governor John Hickenlooper

Grade F

Score 26

Connecticut

Governor Dan Malloy

Grade D

Score 49

Delaware

Governor Jack Markell

Grade F

Score 36

Florida

Governor Rick Scott

Grade D

Score 47

Georgia

Governor Nathan Deal

Grade C

Score 50

Hawaii

Governor Neil Abercrombie

Grade D

Score 40

Idaho

Governor C. L. "Butch" Otter

Grade B

Score 55

Illinois

Governor Pat Quinn

Grade F

Score 32

Indiana

Governor Mike Pence

Grade A

Score 71

Iowa

Governor Terry E. Branstad

Grade B

Score 56

Kansas

Governor Sam Brownback

Grade A

Score 78

See the remaining scores in the CATO Institute's report.