(Andrew Harrer/Bloomberg)

The GOP request comes as the agency is investigating dozens of political groups established in recent years and continues pressing dozens of tea party-affiliated organizations for information on their activities. It also comes as Senate Democrats urged the IRS Monday to restrict and tighten the rules on Super PACs, or tax-exempt organizations that dabble in political affairs by collecting millions of dollars to run advertisements in support of or against certain political parties or politicians.

In a letter sent Wednesday to IRS Commissioner Douglas H. Schulman, 12 Republican senators said: “It is imperative that organizations applying for tax-exempt status are able to rely on a consistent and foreseeable review structure from the IRS. Any significant changes to the IRS review process should be implemented only after appropriate notice and opportunity for comment from the public and affected parties.”

It is critical that the IRS conduct fair investigations, the senators said, noting that some constituents “have raised concerns that the recent IRS inquiries sent to civic organizations exceed the scope of the typical disclosures required.”

The letter was co-signed by Sens. Orrin Hatch (Utah), Rob Portman (Ohio), Mitch McConnell (Ky.), Charles Grassley (Iowa), Lamar Alexander (Tenn.), Bob Corker (Tenn.), Pat Roberts (Kan.), John Cornyn (Tex.), Kay Bailey Hutchison (Tex.), Jon Kyl (Ariz.), John Thune (S.D.) and Rand Paul (Ky.), who asked agency officials to clarify the purpose and scope of ongoing investigations.

The inquiry comes as most Americans are expressing opposition to the existence of Super PACs: Nearly seven in 10 registered voters would like them to be illegal, according to a new Washington Post-ABC News poll.

Sixty-nine percent of all Americans and voters alike said super PACs should be banned. Just 25 percent said they should remain legal.

Follow Ed O’Keefe on Twitter: @edatpost

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