I still don’t think it’s useful to look at total spend to each “party” vs the spread of spend from each source and what they are targeting.

Party represents what they are targeting, because party lines are how much of our legislation is defined. For example, low taxes on wealth is associated more with Republicans, and less restriction on abortion rights is associated with Democrats. Even if they may sometimes mix across party lines, they tend to have extremely strong correlations between party and policy, so donating to a given party is effectively donating for the policies they tend to represent.

The largest donors donate vastly more to Republicans than they do to democrats.

If you want individual policy, it lines up.

Big-tech PACs donated 2-to-1 toward Republicans and Republican-aligned ad and influence campaigns in favor of data center construction: https://www.industrialinfo.com/news/article/money-votes-and-data-centers-will-political-spending-overcome-rising-public-opposition-to-data-cente--359789

Billionaires have outspent on ads to fight a one-time billionaire's tax in California 250-to-1 https://www.commondreams.org/news/wealth-tax-opponents-spending

Law enforcement PACs spend lots of money on Democrats... https://readsludge.com/2020/06/24/law-enforcement-pacs-give-millions-to-the-politicians-who-set-their-budgets/ ...and Democrats shift to being more pro-police. https://truthout.org/articles/in-2024-platform-democrats-lurch-right-on-policing-and-immigration/

Again, it's not that these issues don't sometimes mix across party lines, the police spending is a good example of that, but generally speaking when a party receives donations, it's because the donors believe they are supporting that party's political positions.