bribe
Persuade (someone) to act in one’s favor, typically illegally or dishonestly, by a gift of money or other inducement.
Buying influence is a crime. Nobody ever gets convicted because politicians have passed laws that prohibit people from clandestinely recording conversations. But if you are giving money to politicians in order to gain some kind of favorable treatment at taxpayers expense, then you and the politician are both committing a crime.
Greasing the skids is corruption. If Trump was greasing the skids with all these donations to the Clintons, then he is corrupt. OTOH, if he was donating to the Clintons because he liked what they were doing, then that would be acceptable behavior.
Cruz just threw the election tonight. His campaign is off the rails. Trump is going to win hands down. Celebrate, but don’t try to make excuses for his donations to the Clintons. Just accept them for what they are.
Trump was favored in Iowa either way. Cruz peaked at the wrong time.
With that said, I am truly agnostic if it’s Trump or Cruz as the nominee. I have a slight preference toward Trump because he knows how to talk tough and deliver.
While there is no prid pro quo with political donations, we all know how this game is played. If influence peddling was illegal, every single politician and lobbyist in DC and beyond would be in jail.