macneil/lehrer productions >> brown: the senate today passed the most significant immigration reform in a generation. good evening, i'm jeffrey brown. >> warner: and i'm margaret warner. on the "newshour" tonight, we examine what did and didn't make it into the final senate bill and the challenge ahead as the fight over immigration shifts to the house. >> brown: then, president obama kicks off a six-day swing through africa. we discuss the past, present and future of the u.s. presence on the continent. >> warner: they're young, they're talented, but the new generation of classical performers are struggling to find work. paul solman reports on how hard economic times haven't deterred some starving artists. >> we don't go into music for the money. we go into music because it's part of our soul. it's part of who we are. it's what we have to do. >> brown: we move ahead to the new battlegrounds in the fight over same-sex marriage on the heels of yesterday's landmark rulings from the...