Reality could be catching up with Rep. Christopher Carney (D-Pa.).

Carney, who prevailed in the conservative northeastern Pennsylvania 10th district in 2006 partly because he faced an ethically challenged incumbent, will struggle to hold onto his seat this fall, a new poll conducted exclusively for Roll Call suggests.

In a head-to-head matchup with his Republican challenger, wealthy businessman Chris Hackett, Carney was supported by 49 percent compared with 45 percent for Hackett. The difference was within the poll’s 4-point margin of error.

The poll of 623 likely voters was taken exclusively for Roll Call Aug. 23-25 by SurveyUSA, an automated polling firm.

The rural district has long been a Republican stronghold, and Carney is the first Democrat to represent it since the Eisenhower administration. President Bush carried the district by 20 points in 2004, and Sen. John McCain (R-Ariz.) led Sen. Barack Obama (D-Ill.) 50 percent to 41 percent in the Roll Call poll.

With Republicans outnumbering Democrats in the district, Carney’s slight edge in the poll was attributed to his support from independents and moderates. He had a 2-1 advantage among self-identified moderates and was preferred by independents by a 5-4 ratio.

While boasting impressive credentials as a national security expert and college professor, Carney benefited immeasurably from the national anti-GOP wave in 2006. But the race really wasn’t about him: He defeated veteran Rep. Don Sherwood (R), who was embroiled in scandal surrounding an allegation that he choked his young mistress.

This cycle, Republicans are trying to label Carney a liberal who is close to Speaker Nancy Pelosi (D-Calif.). That argument could carry some weight: Only 13 percent of those surveyed in the Roll Call poll said they approved of the job Congress is doing, while 76 percent said they disapproved.

But President Bush isn’t much of an asset for the GOP either, carrying a 32 percent approval rating, while 61 percent of voters disapproved.

Neither Carney nor Hackett — who emerged from an expensive and hard-fought Republican primary in April — were particularly well known to the voters. Carney was viewed favorably by 40 percent of those surveyed and unfavorably by 23 percent. But 30 percent were neutral and 6 percent said they had no opinion.

Hackett had a 36 percent to 23 percent favorable/unfavorable rating; 31 percent of voters were neutral, while 11 percent said they had no opinion.

Both candidates will spend heavily to influence voters, and the national political parties are likely to follow suit.

Through June 30, Hackett had spent more than $1.2 million on the race — much of it on the GOP primary — including $740,000 of his own money. He ended June with $267,000 in the bank.

Carney spent $595,000 this election cycle as of June 30 and banked more than $1.1 million.

Even though Carney appears to be in a dogfight, the poll does have some good news for Democrats. Although Obama is unlikely to carry the district in the presidential race, if he makes a stronger showing than 2004 Democratic nominee Sen. John Kerry (Mass.), it suggests that his chances of keeping Pennsylvania, a perennial battleground, in the Democratic column are fairly good. Obama lost the 10th district in the Democratic primary to Sen. Hillary Rodham Clinton (N.Y.).