Subject to subsection (b), the provisions of this Act, and of rules prescribed under this Act, supersede and preempt any provision of State law with respect to election to Federal office.

Notwithstanding any other provision of this Act, a State or local committee of a political party may, subject to State law, use exclusively funds that are not subject to the prohibitions, limitations, and reporting requirements of the Act for the purchase or construction of an office building for such State or local committee.