Picture of Sophie and Tycho!
On FLIP THE SENATE -
I found oath.vote very useful to help decide what campaigns to contribute to.
Try these links:
For lower level candidatse that help bring out the vote your money might be most useful:
https://app.oath.vote/donate?p=nested--fh
Or if you want to send to the critically races directly:
https://app.oath.vote/donate?p=hs