Virginia Democrats have unveiled a new U.S. House map that aims to give the party four more seats in Congress. The boundaries were revealed even as an ongoing legal challenge makes use of that map for the midterm elections far from certain. The map released Thursday would dilute Republicans’ hold in Virginia’s conservative areas while giving Democrats a better footing in the districts they would like to flip. And it could give Democrats nationwide an edge in the redistricting battle with President Donald Trump that began when he pushed to redraw districts in Republican-controlled states such as Texas.