user: Question: What is the poll source for Vivian Davis Figures at 29% and a lead margin greater than 27?
Columns: ['Poll Source', 'Dates administered', 'Democrat: Vivian Davis Figures', 'Republican: Jeff Sessions', 'Lead Margin']
Types: ['text', 'text', 'text', 'text', 'real']
Sample row: ['Survey USA', 'October 28, 2008', '32%', '65%', 33.0]
SQL:

assistant: SELECT "Poll Source" FROM "Table" WHERE "Lead Margin" > 27.0 AND "Democrat: Vivian Davis Figures" = '29%';