Not so sure. Phillip Agee did a pretty good job of that and we’re still here.
The problem is that the granting of a security clearance is an extremely subjective process. To give the power to a President or Congress to deny a security clearance to any candidate for national office would be to effectively ensure that the party in power would remain in power forever.
I cannot verify the accuracy or integrity of the source.
http://www.politicalpeon.com/2008/09/barack-obama-senate-committees-and.html
Committee Membership
Barack Obama sits on the following committees:
Member, Senate Committee on Foreign Relations
Chairman, Subcommittee on European Affairs
Member, Subcommittee on African Affairs
Member, Subcommittee on East Asian and Pacific Affairs
Member, Subcommittee on International Development and Foreign Assistance, Economic Affairs and International Environmental Protection
Member, Senate Committee on Health, Education, Labor, and Pensions
Member, Subcommittee on Children and Families
Member, Subcommittee on Employment and Workplace Safety
Member, Senate Committee on Homeland Security and Governmental Affairs
Member, Subcommittee on Ad Hoc Subcommittee on State, Local, and Private Sector Preparedness and Integration
Member, Subcommittee on Investigations
Member, Subcommittee on Federal Financial Management, Government Information, Federal Services, and International Security
Member, Senate Committee on Veterans’ Affairs