A new GOP poll shows a dead heat between Rep. Mark Critz (D) and attorney Keith Rothfus (R) in southwestern Pennsylvania.

Both candidates scored 38 percent in the survey paid for by the National Republican Congressional Committee and the GOP nominee. Twenty-four percent of respondents reported they were undecided.

Party committees, candidates and outside groups have barraged the airwaves in the district. But in the past few weeks, Democratic groups accounted for more airtime.

Republicans say Rothfus improved his position in the race despite the Democratic ad campaign. In July, Rothfus trailed Critz by 15 points in a similar survey from the NRCC and his campaign. This summer, a trio of Democratic surveys also showed Critz holding a smaller 6 to 10 point lead over Rothfus.

The new numbers underscore the competitiveness of the race. Roll Call rates this race as a Tossup.

The McLaughlin & Associates survey tested 400 likely general election voters in the 12th district from Sept. 19 to 20. The margin of error is 4.9 points.

The survey showed GOP presidential nominee Mitt Romney leading President Barack Obama in the district, 53 percent to 39 percent, with 9 percent undecided.

View the full polling memo below:

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