Martin  O’Malley is on the warpath.

In a campaign season that seems like one endless political brawl, the  Democratic governor of Maryland has emerged as perhaps the sharpest-tongued,  most enthusiastic and aggressive advocate for President Barack Obama’s reelection campaign.

Midway through his second term and as chairman of the  Democratic Governors Association, O’Malley has toured the 2012 swing states — and hit the TV sets of Washington, D.C., and New York — cheerfully lacing into the Republican Party and its presumptive  presidential nominee