To House Democrats, New Mexico’s 1st district has been like Moby Dick to Ahab. Democrats have spent 40 years trying to wrest the Albuquerque-based seat — a perpetual swing district on the presidential level — from the Republicans’ hands.

But a new poll conducted exclusively for Roll Call suggests that 2008 may finally be the Democrats’ year. In the race to replace retiring Rep. Heather Wilson (R), former Albuquerque City Councilor Martin Heinrich (D) led Bernalillo County Sheriff Darren White (R), 51 percent to 46 percent.

The poll of 631 likely voters, conducted Aug. 26-28 for Roll Call by SurveyUSA, an automated polling firm, had a 4-point margin of error.

The race is hardly a slam dunk for Democrats — White is a popular figure in a district whose voters respect law enforcement officials, and Republican Congressional contenders have found a way to win there, often pulling off 11th-hour victories when polls showed them trailing.

But White and Republicans have one apparent political trend to worry about: According to the poll, the 1st district is no longer a swing district in the White House election.

In 2004, Sen. John Kerry (Mass.), the Democratic presidential nominee, carried the district by just 3 points. In 2000, former Vice President Al Gore won by 1 point. But in the Roll Call poll, Democratic presidential nominee Sen. Barack Obama (Ill.) led presumptive GOP nominee Sen. John McCain (Ariz.), 55 percent to 41 percent.

This suggests that White, who is better known than Heinrich, is running against a Democratic headwind in the Land of Enchantment. And if Obama is so far ahead in the 1st district, his chances of carrying New Mexico in November are excellent, because the state’s 3rd district is a Democratic stronghold, and the 2nd district almost always goes Republican in White House elections.

President Bush won the state by fewer than 6,000 votes in 2004, and Gore won it by about 350 votes four years earlier.

Another sign that 1st district voters may be souring on the GOP is the political standing of Wilson, the outgoing Congresswoman. While this week’s previous Roll Call polls showed retiring Reps. Jim Ramstad (R-Minn.) and Terry Everett (R-Ala.) still in good stead with their constituents, Wilson had a net favorable rating of minus-5 points. Forty percent of those surveyed said they had a favorable opinion of Wilson, who narrowly lost the Republican Senate primary in June, while 45 percent had an unfavorable view.

McCain also had a net unfavorable rating; 38 percent of survey respondents said they had a favorable view of the GOP presidential nominee, while 42 percent viewed him unfavorably. Obama, by contrast had a 55 percent to 35 percent favorable/unfavorable rating.

In addition, just 30 percent of the district’s voters approved of the job Bush is doing. Sixty-five percent disapproved.

Those numbers make White’s standing in the poll all the more impressive. In addition to trailing Heinrich by just 5 points, he had a 43 percent to 29 percent favorable/unfavorable rating, with 21 percent of voters neutral and 8 percent had no opinion. Heinrich had a 34 percent to 26 percent favorable/unfavorable rating, with 30 percent neutral and 10 percent with no opinion.

To hold this district, Republicans will try to paint Heinrich as an out of touch liberal. But in the poll he was leading among self-described moderates and among Independents.

Both national political parties are making the 1st district a priority this cycle. Democratic Congressional Campaign Committee Chairman Chris Van Hollen (Md.) is scheduled to be in Albuquerque on Thursday to stump for Heinrich. Michelle Obama, the presidential nominee’s wife, is scheduled to make two appearances in New Mexico on Thursday, including a Women for Obama rally in Albuquerque that Heinrich is expected to attend.