user: ### NOW ANSWER:
Question: What is the term limit for Senator Tom Niehaus? 
Columns: ['District', 'Senator', 'Party', 'Residence', 'First elected', 'Term Limited']
Types: ['real', 'text', 'text', 'text', 'text', 'real']
Sample row: [1.0, 'Steve Buehrer', 'Republican', 'Delta', '2006', 2014.0]
SQL:

assistant: SELECT MIN("Term Limited") FROM "Table" WHERE "Senator" = 'Tom Niehaus';