Barack Obama, the Anti-NAFTA Democratic Candidate, sunk in Hillary Clinton in 2008.
A recent Poll shows unaffiliated voters by a 52% to 24% margin think NAFTA needs to be renegotiated and voters overall are more critical of U.S. free trade agreements than voters eight years ago.

Independent Voters will Decide the 2016 Election
(Image by Washington for Bernie Sanders) Details DMCA
In general, men and those 40 and over are more critical of free trade agreements than women and younger voters. Under 40 voters, Bernie Sanders’ most enthusiastic supporters, are the most likely to be undecided.
Since 2008 the percentage of U.S. Voters registered Independent has increased by approximately 23%, primarily as a result of defections from the Democratic Party.
Critical for Hillary Clinton, the perceived establishment candidate in 2016, to win are the independent voters that believe more than 2 to 1 that NAFTA needs to be renegotiated and the undecided under 40 voters.