His fellow U.S. senators dislike David Vitter more than ever as he continues to denounce them for giving themselves benefits denied to regular citizens.

Vitter evidently doesn’t mind being unpopular on Capitol Hill, as, indeed, he was in the corridors of the State Capitol at the start of his political career. He presumably figures voters won’t hold it against him and might be more inclined to think the maverick politician will protect their interests.

If that is his theory, it seems to be working. Although his keenest supporters cannot point to any great legislative achievements in his Senate career, and he had been caught consorting with Washington prostitutes, he sailed to re-election and is now favorite to be the next governor of Louisiana.

The point of his latest stunt, according to his legion detractors, is to boost his election prospects by embarrassing his colleagues. Maybe it is, but other senators must hate him all the more because he is manifestly right. It is their fault that he has the opportunity to portray himself as the champion of working stiffs while his colleagues award themselves illicit privileges.

Given that the issue is “Obamacare,” and nothing bearing the president’s name will command much support in Louisiana, Vitter would appear to have found himself a winner.

The object of Vitter’s crusade is what he calls an Obamacare exemption for members of Congress and their staffs, which actually leaves them in the same position as most American employees, including those in other parts of the federal government. It allows the federal government to continue contributing 75 percent of their health insurance premium.

But the Obama law clearly made congressional employees ineligible for those subsidies. It may not be fair, and it was evidently unintended. There is no other way to read the law, however.

It came about during Senate debate when Charles Grassley, R-Iowa, introduced an amendment scrapping the health insurance program covering members of Congress and their staffs. Henceforth, they would be required to obtain their insurance through the exchanges set up under Obamacare and thus, Grassley said, “go through the same red tape as other Americans.”

This was evidently a mischievous amendment, for Democrats could hardly reject it and still maintain that the exchanges were just a dandy way to provide the expanded coverage required by Obamacare. They duly embraced it.

Grassley has said it was never his intention to deprive congressional staffers of the 75 percent premium subsidy that is commonly provided by large employers in both the private and public sectors. But the amendment was silent on the issue, and the law says only small businesses can subsidize insurance issued through a government exchange.

Congress members and their employees were nevertheless admitted to the Washington exchange on the strength of a spectacularly fraudulent application. It certified that Congress had fewer than 50 employees, and, according to Vitter, included “fake names, birthdays (and) zip codes.” Which congressional staffers concocted such a flagrant misrepresentation, and how it could ever have passed muster, are questions to which taxpayers might feel entitled to an answer.

But the Washington exchange, when it released the relevant paperwork in response to a freedom of information request, had blacked out the signatures. Vitter’s bid to subpoena the unredacted documentation was voted down by a Senate committee.

This must be one of the sweetest defeats of his career. He refuses the subsidy for himself and his staff, while his colleagues accept it and draw a veil of secrecy over how it was finagled. He emerges as the bold crusader for open and even-handed government. That, presumably, was the intention throughout, for he always had an eye for what plays well with registered voters, and to hell with his colleagues. That much was obvious way back when he took credit for introducing term limits in the state legislature.

Still, if his current campaign did succeed, it would be most unfair to congressional staffers, who don’t earn all that much and could hardly afford the extra $5,000 or so it would cost each of them if they could not get subsidized coverage they have always enjoyed. Their bosses would presumably have to up their salaries to cover the extra costs, so the taxpayer would come out about even in the end.

But that is not Vitter’s concern. The health care law dealt congressional staffers a bad hand, but it gave him another opportunity to break ranks with the professional political class. He seized it with the usual aplomb.

James Gill’s email address is jgill@theadvocate.com.