The economy had been voters' chief worry for the last six years, Gallup says.
A strong majority said they were contacted by campaigns too many times and saw too many ads.
The campaign post-mortem is "an admonishment to Democrats," a pollster says.
Recent polls found growing support for ties among Cuban-Americans and nationally.
No Republican presidential contender is within 5 percentage points of Clinton.
Rep. Cassidy (R) leads Sen. Landrieu (D) 56-41 percent in Rasmussen poll.
Thirty-six percent have a favorable view, dropping the party below the GOP.
Still, Rep. Donna Edwards said the results won’t be a “disaster” for Democrats.
Justin Sink 11/03/14 11:48 AM EST
Forty-four percent say they like the president, down from 60 percent in 2012.
Rebecca Shabad 11/01/14 06:05 AM EDT
The persistent dissatisfaction could sink Democrats on Election Day.