Maryland Gov. Martin O'Malley slammed Virginia Gov. Bob McDonnell on his state's budget decisions, job growth and voter identification laws Monday -- and he even challenged him to a push-up contest.

In an interview on WTOP, the Maryland Democrat criticized the "gimmicks" McDonnell has used to balance the budget, "including sometimes short-funding their pension obligations," and the practice of publicly lauding a budget surplus.

"One thing we don't do in Maryland is ... if we finish a month with more cash on hand than might have been projected, we don't light off confetti cannons, call a press conference, pat ourselves on the back and say, 'By golly, we have a surplus.' Maybe we should," O'Malley said.

He also criticized McDonnell's reluctance to tax the wealthy.

"Gov. McDonnell is a sworn opponent of asking millionaires to pay anything more for anything."

O'Malley created a "millionaire's tax" that expired in 2011, a surcharge that economists said prompted wealthy residents to flee the state. This year, he approved an income tax increase on all Maryland residents earning more than $100,000.

He claimed his state is stronger on post-recession job creation than Virginia, with Maryland regaining 67 percent of the jobs lost in the downturn and Virginia regaining 63 percent.

In response, McDonnell spokesman Tucker Martin pointed to the difference in the two states' unemployment rates. Though traditionally the two have had similar unemployment rates, Maryland's is 7.1 percent while Virginia's is 5.9.

In the last year, Virginia also added three times as many jobs as Maryland, Martin said, pointing to data from the U.S. Bureau of Labor Statistics. At the same time, Northern Virginia created more than 22 times as many jobs as Washington's Maryland suburbs.

While Maryland has had a "slight edge" over Virginia on job creation recently, most long-term statistics favor Virginia, said Anirban Basu, chairman and CEO of Baltimore economic consulting firm Sage Policy Group. "As of this moment in economic history, Virginia is better prepared to deal with the federal cutbacks and tax increases likely to come -- and from a business reputation perspective, it's not even close."

Virginia's lower tax rates also help attract business, Martin said. "Maryland keeps raising taxes, and people and businesses keep leaving. Virginia keeps taxes low, and people and businesses keep moving in."

Basu agreed that Maryland's high tax rates could cost the state jobs, especially in the event of federal cutbacks. "It's just that at some point, a state's tax rates become so high as to become noncompetitive, and Maryland may have passed that point."

O'Malley's criticism didn't end with fiscal policy. He called Virginia's new voter ID laws "voter oppression laws" and insisted that Maryland doesn't discourage people from voting. Virginia's new laws require voters to bring some sort of identification, such as a driver's license or a utility bill, to polling stations.

As the interview wrapped up, O'Malley challenged McDonnell to a competition of physical strength.

"We can have a discussion about how we can work together to create jobs and opportunity now, and it can be followed immediately by a push-up contest."

But Martin said McDonnell won't be taking O'Malley up on his challenge.

"Governors have their own, more gubernatorial, version of a push-up contest. It's called the state unemployment rates," Martin said. "Spoiler alert: Virginia wins."