Magellan Strategies, a Republican polling outfit, has a new poll out on the U.S. Senate race in Louisiana.

And the results of the poll indicate that nothing Charlie Melancon has attempted in an effort to close the gap between incumbent David Vitter and himself is working. Vitter maintains a dominating 18-point lead over Melancon, whose support seems frozen in the mid-30’s.

Vitter’s 51.9 percent-to-33.7 percent advantage over the Democrat in the poll, conducted on Sunday, September 19 with 1,232 respondents, cuts across a number of demographic lines…

• Vitter’s overall approval number is plus-12, with 49 percent approval and 37 percent disapproval.
• Melancon’s is 18 points underwater, with 28 percent approval and 46 percent disapproval.
• Melancon’s cause is lost in no small measure due to the awful reputation of President Obama in Louisiana. Some 61 percent express disapproval of Obama, against just 33 percent approval.
• Vitter beats Melancon 57-30 among men.
• Vitter beats Melancon 48-37 among women.
• Vitter beats Melancon 86-5 among Republicans.
• Melancon only beats Vitter 51-34 among Democrats.
• Vitter beats Melancon 52-24 among independents.
• In the 18-44 age group, Vitter beats Melancon 42-41.
• In the 45-54 age group, Vitter beats Melancon 52-33.
• In the 55-64 age group, Vitter beats Melancon 51-35.
• In the 65-plus age group, Vitter beats Melancon 59-28.
• Vitter beats Melancon in every congressional district but the 2nd (Joseph Cao’s district in New Orleans). In Melancon’s 3rd District, Vitter’s 60-29 lead is almost as big as the 64-22 lead he holds in the 1st District,from which Vitter was a congressman before being elected to the Senate in 2004.
• Vitter triples Melancon, 66-22, among white voters.
• Among black voters, Vitter is polling a poor eight percent. But Melancon’s strength isn’t overly impressive; he’s getting 73 percent, with 8.1 percent going to minor candidates and 11.1 percent undecided.

The poll’s sample was 56 percent Democrat, 30 percent Republican and 13 percent independent, which largely mirrors the makeup of the electorate.