Dem pollster: Clinton showed that being against Trump is not enough to win

Democratic pollster Carly Cooperman on Wednesday pointed to Hillary ClintonHillary Diane Rodham ClintonThe Memo: Polls flash warning signs for Trump Polls suggest Sanders may be underestimated 10 declassified Russia collusion revelations that could rock Washington this fall MORE's 2016 presidential bid to argue that opposing President TrumpDonald John Trump Former US ambassador: 'Denmark is not a big fan of Donald Trump and his politics' Senate Democrats push for arms control language in defense policy bill Detroit county sheriff endorses Booker for president MORE alone is not enough to win an election.

"With Hillary Clinton, we saw that just being against Trump isn't enough," Cooperman, who is a partner at Schoen Consulting, told Hill.TV's Joe Concha on "What America's Thinking."

“There is so much anger and passion in the Democratic Party right now to come out against Trump, but I do not think that will be enough," she continued. “The Democrats need more than just that, and they need to have ideas that they're articulating in terms of immigration and the economy."

Cooperman's comments come as Democrats prepare to face off against Republicans in the November midterm elections, with Republicans seeking to defend a narrow majority in the Senate and fend off Democrats trying to retake the House.

Democratic candidates and incumbents have recently lashed out against the Trump administration's controversial "zero tolerance" immigration policy that led to the separation of migrant families at the U.S.-Mexico border, among other criticisms.

— Julia Manchester