Illinois Democrats said the Legislature will return to Springfield to redraw political districts that will be used for legislative elections over the next decade, this time using data from the 2020 census. The announcement Friday came as Republicans said census data released last week show the maps that majority Democrats approved and Gov. J.B. Pritzker signed earlier this year amounted to an unconstitutional power grab. Democrats used population estimates, not the actual census, to draw the boundaries — a move that …