At the rally , she sang a cover of John Lennon 's `` Imagine '' saying `` I 'm not going to ( play ) one of my songs tonight because tonight is not about me , it 's about you . '' At the Human Rights Campaign Dinner , held the same weekend as the rally , she performed a cover of John Lennon 's `` Imagine '' declaring that `` I 'm not going to ( play ) one of my songs tonight because tonight is not about me , it 's about you . ''