This is helpful for a variety of topics covered in class including campaigning, ideology, and the battle for the 2016 Republican presidential nomination in historical context.
The image comes from 538 - click here for the post.
This gets a bit geeky, but the story points out three separate ways that a candidate ideology can be measured.
DW-Nominate scores - which are based on a candidate’s voting record in Congress
CFscores - based on who donates to a candidate
OnTheIssues.org scores - based on public statements made by the candidate