Colorado Democrats and Republicans braced for election results Tuesday night that will help illuminate the depth and endurance of Democrats’ control of the state Capitol and whether Republicans here can find a toehold in a state that’s steadily turned blue. Democrats entered Election Day just one Senate seat shy of a supermajority in each chamber of the state legislature, with an eye on flipping three seats in particular: Senate Districts 5 and 6, both in the southwestern part of the state; and Senate District 12, in El Paso County.