Here is a review of Marquette Law School polling from August 2019 to August 2020 in Wisconsin. All polls are state-wide samples of registered voters, with about 800 respondents per poll (1000 in Feb.) and a margin of error of about +/- 4 percentage points. Details of each survey and full methodology statement are available at https://law.marquette.edu/poll/category/results-and-data/

This analysis looks at the composition of “Biden Republicans”, those you identify as Republicans or independents who lean Republican, but say they will vote for Joe Biden rather than Donald Trump. While cases are limited we also look at Trump Democrats.

Who are the Biden Republicans in Wisconsin

There is strong party loyalty on both sides in Wisconsin. Table 1 shows vote by party identification among registered voters interviewed between August 2019 and August 2020.

Table 1: Vote by party in Wisconsin, Aug. 2019-Aug. 2020 (Cell percentages)
zpid5 Biden Trump Neither Don’t know Refused
Rep 1.8 26.5 0.4 0.5 0.1
Lean Rep 2.0 12.7 0.7 0.5 0.1
Ind 3.2 3.0 1.4 0.8 0.3
Lean Dem 13.8 0.7 1.0 0.5 0.1
Dem 26.6 0.8 0.5 0.4 0.2
Other/None 0.4 0.4 0.1 0.3 0.3

There are, in fact, very few Republican or independents who lean Republican who have said they plan to vote for Biden, a total of 313 out of 8230, or 3.8 percent of all registered voters. The margin of error for this subsample is +/- 6.7 percentage points.

There are even fewer Trump Democrats, just 129 of 8230 or 1.6 percent of all registered voters.

While the sample size is small it is sufficiently interesting to get a profile of these Biden Republicans and compare them with the composition of all Republicans and independents who lean Republican. This is done in Table 2, showing the composition of each group.

Table 2: Composition of Biden Republicans vs all Republicans in Wisconsin, Aug. 2019-Aug. 2020
Group Of Biden Reps Of all Reps Difference
Conservative 28 53 -25
Very conservative 4 17 -13
White, male, non-college 20 32 -12
Follow politics: most of the time 55 67 -12
Subjective Rural 32 43 -11
High school 23 30 -7
Married 59 66 -7
Rest of MKE 31 37 -6
Male 49 55 -6
50-59 22 28 -6
Attend weekly or more 34 39 -5
Rest of state 20 24 -4
Exurbs and large towns 19 22 -3
60-69 14 17 -3
White 87 90 -3
Associates 13 16 -3
40-49 12 14 -2
70+ 14 16 -2
Born again 25 27 -2
Attend few/year 17 19 -2
Union member 4 6 -2
Isolated rural 9 10 -1
Some college 19 20 -1
Farmer 10 11 -1
Suburban core 34 34 0
Post-BA 9 9 0
Catholic 32 32 0
Non-union household 87 87 0
Small town 12 11 1
Hispanic 4 3 1
Other race 5 4 1
White, female, non-college 28 27 1
Other religion 7 6 1
Attend seldom 16 15 1
Very liberal 1 0 1
Non-farm 90 89 1
Not HS 4 2 2
Mainline 26 24 2
No religion 10 8 2
MKE City 7 4 3
GB/A 25 22 3
Black 4 1 3
Widow/Div/Sep 24 21 3
Attend monthly 19 16 3
Union household 8 5 3
Follow politics: now and then 10 7 3
Follow politics: hardly at all 7 4 3
msn 17 13 4
Principal city 27 23 4
White, female, college 17 13 4
Non-white 14 10 4
Attend never 14 10 4
Liberal 6 2 4
Subjective Suburban 40 35 5
Never Married 17 12 5
Subjectuve Urban 27 21 6
Female 51 45 6
18-29 17 11 6
White, male, college 22 16 6
Follow politics: some of the time 28 21 7
30-39 21 13 8
Bachelors 32 24 8
Moderate 58 25 33

Who are the Trump Democrats in Wisconsin?

Here the estimates are much more tenuous with only 129 Trump voters who are Democrats or independents who lean Democratic. The margin of error for this subsample is +/- 10.7 percentage points so the results are at best suggestive rather than precise.

Table 3 shows the composition of Trump Democrats compared to all Democrats (including thos who lean Democratic) in Wisconsin polling from August 2019-August 2020, among registered voters.

Table 3: Composition of Trump Democrats vs all Democrats in Wisconsin, Aug. 2019-Aug. 2020
Group Of Trump Dems Of all Dems Difference
Follow politics: most of the time 42 67 -25
Female 41 62 -21
Liberal 20 33 -13
White 70 81 -11
White, female, non-college 17 28 -11
White, female, college 11 22 -11
MKE City 4 12 -8
70+ 9 17 -8
Post-BA 7 15 -8
Very liberal 8 14 -6
60-69 14 19 -5
Attend monthly 8 13 -5
Non-union household 77 82 -5
Non-farm 89 94 -5
Exurbs and large towns 12 16 -4
No religion 22 26 -4
Attend seldom 16 20 -4
Rest of MKE 23 26 -3
Some college 15 18 -3
Rest of state 20 22 -2
Subjective Suburban 33 35 -2
Union household 4 6 -2
Subjectuve Urban 32 33 -1
Isolated rural 6 7 -1
Black 7 8 -1
Bachelors 25 26 -1
Never Married 21 22 -1
Mainline 25 26 -1
Other religion 8 9 -1
Attend never 23 24 -1
Principal city 40 40 0
Small town 8 8 0
30-39 13 13 0
Not HS 2 2 0
Married 53 53 0
Very conservative 1 1 0
msn 24 23 1
Follow politics: hardly at all 5 4 1
50-59 23 21 2
White, male, college 15 13 2
Widow/Div/Sep 26 24 2
Hispanic 8 5 3
Born again 15 12 3
Subjective Rural 35 31 4
Suburban core 34 30 4
Associates 16 12 4
Catholic 28 24 4
Attend few/year 24 20 4
Moderate 44 39 5
Farmer 11 6 5
18-29 22 16 6
40-49 19 13 6
Attend weekly or more 29 23 6
Other race 13 5 8
Union member 18 10 8
High school 35 26 9
White, male, non-college 26 17 9
Non-white 29 19 10
Follow politics: some of the time 34 22 12
Follow politics: now and then 19 7 12
GB/A 29 16 13
Conservative 25 9 16
Male 59 38 21