Maryland Gov. Martin O'Malley has become a punching bag for Republicans, taking it on the chin from leading politicians, strategists, analysts and conservative commentators as he ramps up his role in the national campaign.

By contrast, Republican Virginia Gov. Bob McDonnell has not inspired the same level of vitriol from Democrats, even though, like O'Malley, he leads his party's governors association.

The difference in attitudes toward the two Potomac governors comes down to their personalities and political ambitions.

Some attacks
"Let [O'Malley] go out there and say let's tax everybody more; let's spend everything we got; we are really concerned about the state and local government employees," Karl Rove, a former top adviser to President George W. Bush told Maryland Republicans last week. "I want to see how far that goes. Even in the Democratic primary, they aren't that dumb."
Republican Governors Association spot: "The largest tax hike in state history. A 'tax-raising legacy.' Taxpayers moving to other states. Sound familiar?"

"He's more gentle," University of Virginia political scientist Larry Sabato said of McDonnell. "He prefers that politics be sporting rather than vicious. It's one reason why, ironically, some people on the right have been criticizing him -- they don't think he's tough enough."

While O'Malley has not hesitated to slam what he views as right-wing extremism in today's GOP, McDonnell, a top surrogate for Republican presidential nominee Mitt Romney, mostly focuses on the economy and on regulations that he thinks stifle job creation.

And O'Malley, unlike McDonnell, has stoked heightened speculation about a potential run for the White House in 2016, making him an even bigger target for his political opponents, according to Sabato.

Some analysts think O'Malley benefits politically from his combative style.

"The best way to make a name for yourself nationally is to pick some good fights," said Thomas Schaller, a political science professor at the University of Maryland, Baltimore County. "When you have people the caliber of Karl Rove attacking you, it moves you into the big leagues."

Speaking to Maryland Republicans last week, Rove dismissed O'Malley as a tax-and-spender who thinks economic growth can be achieved through investments in the public sector.

Even McDonnell, who typically enjoys good-natured ribbing with his regional rival, got into the O'Malley bashing. The Republican Governors Association released an ad ahead of the Wisconsin recall election highlighting O'Malley's push to raise taxes and linking his record to Milwaukee Mayor Tom Barrett, who was defeated by Republican Gov. Scott Walker.

"Governor O'Malley is a vocal and unabashed proponent of the theory that economic recovery will come via higher taxes and bigger government," said Tucker Martin, a spokesman for McDonnell. "Well, a whole lot of people beg to disagree with that assumption."

O'Malley's office dismissed the heightened attention as normal political posturing before a tightly contested election.

"The attacks are focused on his defense of the president's record," said O'Malley spokeswoman Raquel Guillory. "We expect the rhetoric by the other side to heat up as the election draws closer."