By at least one measure, David Vitter ranks No. 1 in the U.S. Senate.

Vitter, a Republican from Metairie hoping to win election as governor Saturday, rates as the most prolific bill-filer of the Senate’s 100 members.

In the current session of Congress, which started in January, Vitter has introduced 110 bills as the lead sponsor, well ahead of the 53 put forth by the Senate runner-up, Ron Wyden, D-Ore., according to the late Wednesday tally of the official Website.

Vitter spoke on the Senate floor Tuesday in support of his latest bill, the Syrian Refugee Verification and Safety Act, a measure to block the immigration of refugees from Syria until adequate safeguards against terrorist infiltration are put in place.

Of those 110 bills, two have passed the Senate: a measure rolling back the raises approved for the CEOs of the federal mortgage agencies Fannie Mae and Freddie Mac, and another, called the Steve Gleason Act in honor of the former New Orleans Saints player afflicted with amyotrophic lateral sclerosis, that restores Medicaid and Medicare coverage for speech-generation devices used by ALS patients and others. The Gleason Act cleared the House as well and has been signed into law.

Since entering the Senate in 2005, Vitter has filed 457 bills as lead sponsor; 11 have passed the Senate, and four have been signed into law. The low percentage of success, though, is not necessarily an accurate indicator of his effectiveness. A senator’s proposals may get folded into larger bills, or a companion House measure may prevail, bearing the name of its House sponsor. Members also may sponsor amendments that prove critical, or they may play a key role as a cosponsor of a bill.

In an October 2014 survey of the 2013-14 Congress, the two bills signed into law that had been sponsored by Sen. Patrick Leahy, D-Vt., were enough to give him the lead in that category. And in her 18 years in the Senate, from 1997 to 2015, Democrat Mary Landrieu, of New Orleans, sponsored 337 bills, with 21 passing the Senate and nine of those becoming law.

A firm conservative, Vitter, 54, has pushed many legislative initiatives reflecting his deep-red ideological bent. He has introduced bills to repeal birthright citizenship and to speed the deportation of unaccompanied children immigrating illegally — and just last month, his bill to punish “sanctuary cities” that excuse illegal immigrants from federal enforcement directives fell short of passage on the Senate floor due to opposition from Democrats. He has proposed cracking down on abortion providers, reining in environmental regulations and shielding schools from federal sanctions for abandoning the Common Core educational standards.

Vitter cites his work on coastal restoration, hurricane relief and highway funding among his Senate accomplishments, as well as the assignment of a four-star general to Barksdale Air Force Base, the construction of new Veterans Affairs medical clinics in Lafayette and Lake Charles and the inclusion of a community banker on the Federal Reserve Board.

Another Vitter focus is the Affordable Care Act, the 2010 health law that is the signature legislative achievement of Democratic President Barack Obama and is widely known as Obamacare. Vitter has filed a bill to repeal it altogether. Short of that, he’s put in a bill to tighten up on the ACA subsidies that help low- and middle-income Americans buy health insurance. And Vitter has introduced a bill to force the president, vice president and Cabinet officers to get their coverage through “Obamacare.”

It is his dogged pursuit of another “Obamacare”-related issue that one former congressional staffer long involved with the Louisiana delegation points to as “classic Vitter.”

When the 2010 law was working its way through Congress, then controlled by Democrats, a Republican senator inserted an amendment to require members of Congress and their staffers to obtain their health insurance through an ACA exchange. That removed them from the insurance plan that covers other federal workers and that picks up about 70 percent of the cost, under an arrangement typical for large employers. A later attempt by the same senator to alter that provision failed, and it remains in the 906-page law.

Under ACA rules, the federal government, as a large employer, effectively could not contribute to the cost of insurance purchased through an ACA exchange offering individual and family coverage plans. The federal Office of Personnel Management instead directed the congressional employees to the ACA small-business exchange operated by the District of Columbia, which allows for employer contributions. The House and Senate duly filed paperwork in 2013 with the D.C. small-business exchange, and thousands of employees enrolled.

But neither the House nor the Senate comes close to qualifying as a small business under the law.

Vitter repeatedly attacked the congressional work-around during the 2013-14 Congress, filing bills and amendments to overturn it, without success. In March 2015, in a Senate controlled by a new Republican majority, he won approval of a measure to end the set-up, but that was in an amendment to a budget plan that is nonbinding.

Meanwhile, a conservative legal group had filed a lawsuit over the deal, bringing forth copies of the House and Senate applications to enroll in the D.C. small-business exchange. They are riddled with misrepresentations, including that each chamber employs just 45 people and that the applicant is a state or local government. The applications were signed by whoever submitted them, but the signatures were blacked out in the documents released to the legal group. Vitter’s requests for full disclosure from the House and Senate administrations — both controlled by Republicans — were either stonewalled or ignored.

The new Republican majority put Vitter in the chair of the Senate Small Business and Entrepreneurship Committee, and in April, Vitter sought a committee subpoena for the unredacted documents. In a stunning setback, five senators from the committee’s Republican majority joined its Democratic minority to reject his request on a 14-5 vote.

“I think you’ve got compelling evidence that wrongdoing has been committed here,” James Risch, R-Idaho, said in the committee meeting. But he voted against Vitter, arguing that issue was a distraction better left to federal prosecutors.

“I joined this committee because I want to do things for small businesses,” Risch said — something he said the committee had tried hard to achieve in his seven years on it, almost all under Democratic leadership. “This is really going to take our eye off the ball.”

Mike Enzi, R-Wyo., also voted no. “I do want to have insurance, and I want to make sure my employees have insurance,” Enzi said.

But Vitter has said that’s not the issue. “Before we get to policy arguments, I think we should be following the law,” he has said. “I have a big problem with just ignoring the law because it’s inconvenient.”

He also wants to make a case about “Obamacare” in general.

“I think the chefs should have to eat their own cooking,” he has said.

“Vitter is good at latching onto one small thing and hitting it again and again,” the former congressional staffer said. “He’s relentless in that way.”

One well-connected Capitol Hill veteran — who, like the staffer, did not wish to be quoted by name — said Vitter’s relationships with his Senate colleagues are similar to those from 20 years ago among Vitter and his fellow members of the Louisiana Legislature, where Vitter served before first coming to Congress as a U.S. representative in 1999. Vitter was regarded in Baton Rouge as less than chummy, and he spearheaded a term-limits law and a requirement for public disclosure of Tulane University legislative scholarships that rubbed some in the state Capitol the wrong way.

A May article on the “Obamacare” committee fiasco in Politico, a widely read inside-the-Beltway news outlet, called Vitter “one of the most disliked members” of the Senate, viewed as a grandstanding show horse by his colleagues. And the New York Times last week referred to him as “a Senate loner” in an article on the implications of the governor’s race for the next Congress.

“I sure stand up for things I believe in and fight hard for things I believe in,” Vitter said. “I stand up and fight, particularly against the political status quo, the insiders, when I think they’re doing wrong by normal citizens.”

Vitter pointed to his work across partisan lines as proof against those negative characterizations of him.

As the lead cosponsor of a far-reaching bill to upgrade and strengthen federal regulation of toxic chemical products, Vitter has teamed up with the measure’s Democratic sponsor, Tom Udall, of New Mexico, negotiating compromises and rounding up broad support for the measure, which awaits Senate floor action. He worked with liberal Democrat Barbara Boxer, of California, on a major water public-works bill that included several big Louisiana projects; it was signed by Obama in 2014. And he has collaborated with Democrats Sherrod Brown, of Ohio, and Elizabeth Warren, of Massachusetts, on bank regulatory proposals.

“I don’t agree with him on much of anything except on these banking rules,” Brown said late last year. “He’s been a natural partner for me on this, although on almost every other issue we probably cancel each other’s votes,” he said.

“It’s been a real productive partnership,” Vitter has said of his work with Brown. In other respects, Vitter said, “We disagree on a whole of things, to state the obvious.”

Bob Livingston, a D.C. lobbyist and former Republican congressman from New Orleans who has known Vitter for years, said, “He’s been a damned good senator for Louisiana.

“He has always been attentive at every meeting I’ve ever had with him,” Livingston said. “He’s done his homework ahead of time, he’s been knowledgeable, and if it’s within his power, he’s acted.”

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