You ask which party was being partisan in the 10-8 Alito vote.

In the Ginsburg vote and the Alito vote Republicans on the Senate Judiciary Committee voted 100% for the nominees of the incumbant presidents.

In the Ginsburg vote and the Alito vote Democrats on the Senate Judiciary Committee voted 100% and 0%, respectively, for the nominees of the incumbant presidents.

Now which party was being partisan? Duh, this is a hard one.