Few observers would ever have dreamed that GOP Rep. Ralph Hall's Texas seat is anything but completely safe. He's occupied it for more than a quarter-century. CQ Politics rates it "Safe Republican." And the district, which is around 100 miles from Hall's friend President Bush's Crawford ranch, is deep red: Seventy percent of its voters went for Bush in 2004. But now a new poll obtained by Election Central which was commissioned by Hall's Dem foe, history professor Glenn Melancon, suggests that Hall may be vulnerable after all. The poll finds that among likely voters Hall leads Melancon by seven points, 48%-41%. You can read the poll in our TPM Document Collection. More after the jump.

The poll -- which was overseen by two local professors, political science professor Nathan Bigelow and sociology professor Janet Huber Lowry -- notes that Hall has gotten a minimum of 58% of the vote in the last five straight elections. But the numbers it finds this time around are different. It surveyed 400 registered voters without providing descriptions of the candidates, and found the above-mentioned 48%-41% spread among those who say they will "certainly vote."

The Melancon campaign also points to another number in the poll they hope bodes well for them: Only two years ago, Hall pulled 68% of the vote, which means that if today's poll is accurate, Hall's registered a drop of 20%. "That's huge," Melancon campaign manager David Marlett tells Election Central. "This is someone who's been here for a lot of these people's voting lives. We've been saying all along that they're just absolutely fed up."

Presuming for the moment the poll is within striking distance of the candidates' actual levels of support, what could account for such a drop? Hall's committed a few unsightly gaffes of late. He recently stumbled badly in efforts to explain away his ties to lobbyist Jack Abramoff. Meanwhile, Melancon has been blasting Hall for a statement he placed in the Congressional Record in 1997, when he slandered a teen sex slave.

Hall, who's 83, also recently insisted that he'd take his controversial trip to the Marianas with Abramoff all over again, and he continues to be dogged by a comment he made some time ago in which he suggested that Baghdad should have been leveled so Iraqis knew they were whipped. Those comments, plus stances such as his refusal to require Congress to pay for tax cuts, cost Hall the backing of the Dallas Morning News, which refused to endorse a candidate in the race.

The Melancon campaign concedes that it's extremely low on funds and can't afford to go up on the air. It's always tough -- particularly in the absence of independent polling -- to gague the accuracy of internal polls such as this one, and dislodging Hall in such a conservative district continues to be a massive uphill struggle. But the Malencon camp is hoping that Hall's record and recent screw-ups, combined with the general tide against Bush and the GOP, will finally lead voters to take a chance on someone new after a quarter-century. "We are the little campaign who could -- everybody said Hall's unbeatable," Marlett says.

We'll be posting the internals of the poll soon.

Update: The poll is right here.