President Trump’s ability to slide his supporters to the left or right will face a major challenge if he lives up to what Democratic congressional leaders described on Wednesday night as the beginnings of an agreement to prevent the deportation of nearly 800,00 undocumented young immigrants and to strengthen border security without building a wall.

Barber and Pope’s paper expands on recent work by David E. Broockman and Daniel M. Butler, “The Causal Effects of Elite Position-Taking on Voter Attitudes,” which was published in the American Journal of Political Science. Broockman and Butler, who are political scientists at the Stanford Graduate School of Business and the University of California-San Diego, found that

Voters often adopted the positions legislators took, even when legislators offered little justification. Moreover, voters did not evaluate their legislators more negatively when representatives took positions these voters had previously opposed, again regardless of whether legislators provided justifications. The findings are consistent with theories suggesting voters often defer to politicians’ policy judgments.

Along similar lines, Christopher Achen and Larry Bartels, political scientists at Princeton and Vanderbilt, reject traditional views of democratic elections in their new book, “Democracy for Realists: Why Elections Do Not Produce Responsive Government.” Achen and Bartels argue that the “familiar ideal of thoughtful citizens steering the ship of state from the voting booth is fundamentally misguided.”

In the conventional view, democracy begins with the voters. Ordinary people have preferences about what their government should do. They choose leaders who will do those things, or they enact their preferences directly in referendums. In either case, what the majority wants becomes government policy — a highly attractive prospect.

Achen and Bartels dismiss this “folk theory of democracy” to argue that the more realistic view is that

Citizens’ perceptions of parties’ policy stands and their own policy views are significantly colored by their party preferences. Even on purely factual questions with clear right answers, citizens are sometimes willing to believe the opposite if it makes them feel better about their partisanship and vote choices.

They conclude “that group and partisan loyalties, not policy preferences or ideologies, are fundamental in democratic politics.”

The Barber-Pope study took advantage of Trump’s exceptional propensity during the campaign to take multiple, often contradictory stands on issues. This allowed them to cite two opposing stands Trump had taken on a series of issues in order to test the willingness of Republican voters to follow Trump’s position to the left or right.

The authors conducted a survey with YouGov of 1,300 voters broken into five subgroups, each of which was asked 10 questions using a research design that employed “both ‘conservative’ and ‘liberal’ Trump cues.”

For example:

1. “Do you support or oppose increasing the minimum wage to over $10 an hour?”

2. “Donald Trump has said that he supports this policy. How about you? Do you support or oppose increasing the minimum wage to over $10 an hour?”

3. “Donald Trump has said that he opposes this policy. How about you? Do you support or oppose increasing the minimum wage to over $10 an hour?”