“I would NOT take only “x people voted for Trump” to be ANY kind of indicator of the level of conservative students on campus. Most conservatives I know from all ages didn’t vote for him.”
THIS. I only know one Republican who initially supported Donald Trump. Trump won the Republican primary with a majority of votes, but not a plurality. He was, however, the top Republican candidate for both California and the entire Northeast save Maine, so there are definitely folks in those “Ivy” states who liked him for whatever reason. I’m still struggling with the Trump phenomena. IMO, he won the election because he was a political outsider. If he had run on the Democrat ticket and faced off against Ted Cruze, I think Trump still would have won.
That being said, rather than attempting to start a Young Republicans or YAF that might draw some very right wing students, your daughter might prefer to volunteer to specific causes that support her political beliefs. I have a fairly fiscally conservative daughter who is very liberal on social issues. She will gladly support her school’s Young Democrats at equal rights marches but will debate them on taxes.