Rep. Ben Chandler (D) is out with a new poll today that shows him with a 20-point lead over attorney Andy Barr (R) in the Lexington-based 6th district.

The survey, which was conducted by the Mellman Group for Chandler’s campaign on Sept. 13 and 14, showed Chandler up 53 percent to 33 percent with 14 percent undecided. The poll of 400 likely voters had a 4.9-point margin of error.

Chandler’s poll was in the field at the same time Republicans released a new ad painting Chandler as a “lap dog” of Speaker Nancy Pelosi (D-Calif.). As the electoral environment turned against Democrats this cycle, the NRCC has been increasingly confident that the Congressman’s voting record — specifically his support for the cap-and-trade bill — has made him vulnerable this cycle.

As of last week, the NRCC had spent about $132,000 against Chandler. Meanwhile, third-party groups in the coal community have already indicated they plan to target the Congressman.

But Chandler’s internal poll is the second poll in as many weeks that shows him with a comfortable lead. A Democratic Congressional Campaign Committee poll from Sept. 7-9 showed Chandler up 52 percent to 38 percent on Barr.

The last time Barr released a poll was in June, just weeks after his primary victory, which showed him within 7 points of the Congressman.