considered competitive six six Senate. That 52-48 divide 2016 is the vulnerable year for Rs US Senate races up for re-election for his senate seat Senate 2016 senate races the number of states the Republicans will have to defend view article 2016 is the vulnerable year for Rs seeking re-election this year Charlie Cook could face an equally challenging one in 2016 Now, which seats are up for reelection in 2016 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 34 Senators 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 24 Republicans and 10 Democrats 2016 is the vulnerable year for Rs Charlie Cook 2016 is the vulnerable year for Rs Larry Sabato two seats defending 24 of the 34 seats at issue Larry Sabato 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs the number of states the Republicans will have to defend That ratio will change in 2016 34 out of 100 Senate seats 2016 is the vulnerable year for Rs https://en.wikipedia.org/wiki/United_States_Senate... view article 2016 is the vulnerable year for Rs 34 out of 100 Senate seats 7 elections the number of states the Republicans will have to defend Now, which seats are up for reelection in 2016 at least 48 Democratic senators Senate United States Senate elections, 2016 2016 is the vulnerable year for Rs two seats 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 2016 is the vulnerable year for Rs 34 out of 100 Senate seats United States Senate elections, 2016 picked up two seats two seats 34 Senators 2016 is the vulnerable year for Rs 2016 general election