U.S. Rep. Bruce Braley holds double-digit leads over most likely Republican contenders:
42 - 30 percent over former U.S. Attorney Matt Whitaker;
42 - 29 percent over State Sen. Joni Ernst;
40 - 31 percent over businessman Mark Jacobs;
42 - 27 percent over radio commentator Sam Clovis.
Congressman Braley gets a 35 - 18 percent favorability rating, while 46 percent of Iowa voters don't know enough about him to form an opinion. For the Republicans, 77 to 85 percent of voters don't know enough about the candidates to form an opinion.
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From March 5 - 10, Quinnipiac University surveyed 1,411 registered voters with a margin of error of +/- 2.6 percentage points. Live interviewers call land lines and cell phones.
http://www.quinnipiac.edu/institutes-and-centers/polling-institute/iowa/release-detail?ReleaseID=2019