Sen. David Vitter’s crusade against government contributions to congressional health care plans continues this week with a vote to subpoena documents from the D.C. government, but he may have some dissenters in the Republican ranks.

The Louisiana Republican is the chairman of the Senate Small Business Committee, and he has used his perch to investigate congressional enrollment in the District of Columbia’s small-business exchange, which allowed for a government contribution to congressional health care plans. But his investigation has some members questioning whether this is an issue for his committee.

“I’m not even confident it’s within the jurisdiction of the committee, so I still have serious questions about it,” Sen. Kelly Ayotte, R-N.H., told CQ Roll Call Wednesday. “I have two concerns: whether we have jurisdiction and whether that’s the proper role of this committee.”

Ayotte is one of 10 Republicans and nine Democrats on the committee who will vote Thursday on whether to subpoena the D.C. Health Benefit and Exchange Authority for un-redacted congressional applications to the small-business exchange. A recent taxpayer lawsuit obtained the applications, showing that the House and Senate claimed to have fewer than 50 employees and were also classified as “state/local government,” but the names of the House and Senate employees who verified the applications were redacted.

In February, Vitter asked House and Senate administrators to reveal which employees signed the applications, but administrators did not supply the information. So after months of unanswered requests — and an appeal to Speaker John A. Boehner, R-Ohio, for help — Vitter is making a last-ditch effort to force DCHBEA to comply by issuing a subpoena.

But to do so, Vitter either needs the support of ranking member Jeanne Shaheen, D-N.H., or from the majority of committee members. Shaheen confirmed Wednesday she is a “no,” so Vitter will likely need all the panel’s Republicans to support him.

Vitter issued a statement Tuesday that included a line noting “most committee Republicans” would support the subpoena. But none of the seven GOP committee members approached by CQ Roll Call Wednesday said they would vote in favor of the resolution, though they did not say they would vote against it. The lawmakers either did not want to divulge their vote ahead of time, or were still examining the issue.

“I don’t know yet,” said Sen. Deb Fischer, R-Neb., when asked how she would vote. Asked if there was anything giving her pause, she said, “I certainly enjoy being on the Small Business Committee because of the emphasis that we’ve had on innovation and entrepreneurship and helping people grow their business. And I hope that that will continue to be the emphasis of the committee.”

Democrats echoed the concern about committee jurisdiction over congressional health care.

“I have a hard time understanding how the Small Business Committee has jurisdiction over this issue to start off with,” said Sen. Benjamin L. Cardin, D-Md. “Secondly, this has been very much handled, administratively, with Sen. Vitter and what he’s requesting is not really consistent with the mission of this committee.”

Along with issues of jurisdiction, some Democrats believe the government contribution should remain in place.

“An employer benefit is a standard part of employment of a huge percentage of the private sector,” committee member Edward J. Markey, D-Mass., said, after noting he would vote against the subpoena. “And I think it’s something that is reasonable to have for employees in the government.”

Vitter has long criticized what he calls the “Washington exemption,” or the government contribution to congressional health care plans. Enrolling in the D.C. small-business exchange, rather than the individual exchange, allowed lawmakers and staffers to keep the government contribution.

Critics say the contribution shields members of Congress and their staffs from the effects of the Affordable Care Act. Congress inserted provisions in the legislation before passage that scrambled congressional health care, forcing members and staffs onto the exchanges that were initially intended to provide health plans for those not receiving health care already from an employer, such as small businesses.

“Congress should absolutely not be exempt from living under Obamacare just like the millions of Americans who don’t get a special taxpayer funded subsidy,” Vitter said in a Tuesday statement. “Issuing this subpoena will allow us to find out who is responsible for allowing Congress to receive a special taxpayer-funded subsidy on Obamacare, so we can fix this — and ultimately, end the special exemption.”

According to a Congressional Research Service report, in 2014 the maximum government contribution was $426 a month for individuals and $948 a month for families. The latest figures from DCHBEA indicate 13,700 lawmakers, staff and dependents are currently enrolled in congressional health care plans.

Related:

House Officials Not Impressed With Vitter’s Obamacare Probe

Vitter Extends Deadline for Obamacare Documents From D.C., House, Senate

Vitter Requests Obamacare Documents From D.C., House and Senate

D.C. Government: OPM Trumps Local Law on Congressional Health Care

Obamacare Lawsuit Challenges Congress’ ‘Small Business’ Status

Health Insurance for Congress and Staff: It’s Complicated

The 114th: CQ Roll Call’s Guide to the New Congress

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