Republicans and Democrats are once again at almost even levels, with 27 percent of Americans choosing each one in ways that are increasingly ideologically aligned. The percentage of Republicans who also think of themselves as conservative or very conservative is now at a record high of 77 percent. Democrats have also shifted sharply away from moderation in recent years, with 59 percent now identifying themselves as liberal or very liberal — also a record high. As the parties have moved to the edges, it can feel like a yawning political chasm has been left in their wake.