Rep. Roscoe Bartlett (R-Md.) is playing offense in his reelection bid, going on the air with a television ad attacking the business record of his Democratic opponent, financier John Delaney.

Bartlett is one of the most endangered Republican incumbents in the country, after Democrats in Annapolis redrew his district to include a slice of liberal-leaning Montgomery County. Delaney, the founder of the Chevy Chase commercial finance firm CapitalSource, won the Democratic nod in an upset over the establishment favorite, state Senate Majority Leader Robert Garagiola (Montgomery)

Bartlett’s TV ad, his first of the general election, takes aim at some of the companies that took loans from Capital Source.

“What kind of congressman would John Delaney be?” the ad’s narrator asks. “Delaney’s company owned nursing homes where Medicare inspectors found mistreatment of seniors, including failing to properly administer medication and failing to treat seniors with dignity and respect.

“Delaney’s company also backed a landfill that was shut down for illegally accepting thousands of tons of trash. It even let polluted water runoff flow from the dump. As congressman, John Delaney would serve his interests, not ours.”

The Maryland Republican Party sent out mailers last week that also focused on the landfill charge.

Bartlett’s criticisms echo some that were leveled at Delaney by Garagiola during the Democratic primary. Then, as now, Delaney’s campaign called the attacks wildly off-base.

Delaney’s camp said the landfill company at issue, National Waste Services of Virginia, got loans from CapitalSource, but Delaney’s firm never actually managed the company or the landfill. And the nursing home company, Haven Healthcare, was temporarily owned by CapitalSource after the company could not pay its creditors, but CapitalSource did not operate the nursing homes.

“Given Bartlett’s history, this false attack is as hypocritical as it is outrageous. The only candidate in this race with a record of endangering the public health with contaminated drinking water is Roscoe Bartlett,” said Delaney campaign manager Justin Schall, citing reports two decades ago that Bartlett provided water that did not meet safety standards to tenants of apartments he owned on his farm in Frederick County.