Well, sure he can. The question remains as to whether he would.
Actions speak louder than words. When appointing judges in the past, most have been liberal. One can argue the pool of appointees and the appointment system, but the fact remains that the judges he appointed were mostly liberals.
If you don't want to rely on actions, examine Rudy's words. He says that he is pro-choice. He says: "Presidents, going back to the beginning of the republic, generally appoint people on the Supreme Court that they believe agree with them."
Both Rudy's actions and his words indicate that any appointments to the SC very likely could be liberal thinkers. At this point, his current promises don't mean as much to me as his prior words and deeds.
All dem judges WILL be extremely liberal.