Why can not the 95% of the non-rich do something about it? Stop the "corruption" of the nation by the rich
They have 95% of the vote power to get the problem solved.
The rich only control 5% of the vote.
That depends on which vote you are talking about.
Median wealth of the US house: $765,000.
Median wealth of the US senate: $2.38 million.
Source.
I bet that most people would consider someone with $2.38 million to be wealthy (and half of all senators have more than that!). Those mostly wealthy senators have 100% of the votes that matter right now. Remember, they aren't voting for your best interest, they are often voting for their best interest.
If you are looking at the people who vote in the congressmen, you may be right that they have the power, but they are heavilly influenced by spending (see the Koch brothers effect in the last election) and often have to chose between one wealthy candidate and another wealthy candidate. The public often doesn't have a say.
What about primaries?
Look at what we had to choose from. Not a poor one in that bunch.