Question: how many republican seats are up for election in 2018
[{'answer': 'nine', 'provenance': [{'wikipedia_id': '38680975', 'title': '2018 United States Senate elections', 'start_paragraph_id': 1, 'start_character': 465, 'end_paragraph_id': 1, 'end_character': 469, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]