Question:
51. If the election for U.S. Senator were being held today and the candidates were
Russ Feingold and Ron Johnson, for whom would you vote?

About this Poll
https://law.marquette.edu/poll/wp-content/uploads/2015/04/MLSP28Methodology.pdf

The Marquette Law School Poll was conducted April 7-10, 2015. A total of 803 Wisconsin registered voters were interviewed by a combination of landline and cell phone using random digit dialing (RDD). Interviews were completed with 448 (56%) landline respondents and 335 (44%) cell phone respondents. The data collection was managed by LHK Partners Inc, Newtown Square, PA. The margin of error for a single percentage in a sample of 803 respondents is +/- 3.5 percentage points. For subgroups with smaller sample sizes the margin of error is larger. For Republicans and independents who lean toward the Republican Party, the sample size is 319, with a margin of error of +/-5.6 percentage points. For Democrats and independents who lean toward the Democratic Party, the sample size is 391, with a margin of error of +/-5.1 percentage points. Republican and Democratic presidential primary items were asked of the corresponding party samples.