Ellis Paul, one of the leading voices in American songwriting, will perform at 8 p.m. Saturday, Jan. 1, at One Longfellow Square in Portland. Paul was a principal leader in the wave of singer-songwriters who emerged from the Boston folk scene. Over his career, Paul has built a vast catalog of music that blends poetic imagery and philosophical introspection with memorable melodies. He has shared the stage with such artists as John Mayer, Bill Morrisey, Shawn Colvin and John Gorka. Though he remains among the most pop-friendly of today’s singer-songwriters, his songs regularly appear in hit movie and TV soundtracks. Tickets are $18 in advance, $20 at the door. On Friday, Jan. 7, Le Vent Du Nord will perform at 8 p.m. Tickets are $25 in advance, $28 at the door.