Repeal the 17th Amendment. Most of these types of problems will be solved quickly.
17th is but a start.
Make ‘em telecommute. No donations/solicitations/meetings/etc. from any non-voting-able entity. Make the State responsible for the $$ of their office/security/benefits/etc. Ensure any/every bill is paid by the % of each State population (oil pipeline in AK? CA/NY/etc. pay a larger share...That’ll get eyes on each expenditure).
Got more, but some of us have to work for a living...
Repeal the 17th Amendment!