(ASSOCIATED PRESS) — An “Obamacare” tax on medical devices is falling short of its revenue target because thousands of companies aren’t paying it, according to a government audit released Tuesday.

The audit by the Treasury inspector general for tax administration says the IRS needs to do a better job policing the tax. The tax agency, however, doesn’t have adequate tools to identify which companies owe it, the audit said.

The report could add fuel to efforts to repeal the tax, which is opposed by Republicans and many Democrats.

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