After dropping hundreds of thousands of dollars earlier this year to help conservative state Sen. Andy Harris beat moderate Rep. Wayne Gilchrest in the February GOP primary, the anti-tax group Club for Growth is back on the air this week in Maryland’s 1st district.

The Club for Growth’s political arm spent $100,000 to run two ads in the Baltimore and Salisbury media markets. The ads, which criticize Queen Anne’s County State’s Attorney Frank Kratovil (D) for the cost of his health care plan and his ties to labor unions, both tag the Democrat as “extremely liberal.”

The Democratic Congressional Campaign Committee has dramatically increased its independent spending on the race, with an infusion of more than $300,000 into the district this week alone. The committee’s investment in the district topped $1.2 million as of Wednesday.

Since winning the Democratic primary, Kratovil has been working hard to paint himself as the heir to Gilchrest’s moderate mantle in the Eastern Shore-based 1st district. Kratovil got a major boost in that effort when Gilchrest himself crossed party lines and endorsed the Democrat in early September. Since then, Gilchrest, who received just 33 percent in the bitter three-way GOP primary, has made several appearances with Kratovil and appeared in a commercial in which he says Kratovil “will be independent and he’ll put common sense ahead of politics.”

Since the much-publicized endorsement, the Harris campaign has been working hard to neutralize Gilchrest’s crossing of party lines.

This week, Harris’ camp pounced on statements Gilchrest made at a speech to the League of Conservation Voters when he revealed that he had voted for Maryland’s Democratic Gov. Martin O’Malley in 2006.

Harris’ campaign was quick to rush out a statement assailing the “liberal policies” shared by O’Malley, Gilchrest and Kratovil.

“O’Malley, Kratovil and Gilchrest support higher taxes, more wasteful government spending and amnesty for illegal immigrants — that’s liberal,” said Harris campaign manager Chris Meekins.