Here is the updated ratings ranker including Monday night's Democratic debate on CNN. It ranks 3rd overall in Total Viewers and 2nd in the A25-54 demo for debates this election cycle.
Debate
Network
Total Viewers
A25-54
Jan. 5 Dems
ABC
9,360,000
2,900,000
Jan. 5 GOP
ABC
7,350,000
1,800,,000
Jan. 21 Dems
CNN
4,733,000
1,857,000
Nov. 28 GOP
CNN
4,292,000
1,409,000
Nov. 15 Dems
CNN
3,919,000
1,077,000
Jan. 10 GOP
FNC
3,651,000
1,039,000
Sept. 5 GOP
FNC
3,141,000
854,000
Aug. 19 Dems
ABC
2,799,000
1,046,000
June 3 Dems
CNN
2,714,000
1,050,000
July 23 Dems
CNN
2,552,000
831,000
Jan. 6 GOP
FNC
2,504,000
767,000
May 15 GOP
FNC
2,445,000
664,000
Jan. 15 Dems
MSNBC
2,442,000
875,000
Oct. 30 Dems
MSNBC
2,399,000
738,000
Oct. 21 GOP
FNC
2,367,000
697,000
Sept. 9 Dems
Univision
2,194,000
1,166,000
April 26 Dems
MSNBC
2,164,000
736,000
Aug. 5 GOP
ABC
2,106,000
709,000
June 5 GOP
CNN
1,974,000
689,000
Dec. 9 GOP
Univision
1,822,000
925,000
May 3 GOP
MSNBC
1,705,000
523,000
Sept. 26 Dems
MSNBC
1,449,000
539,000
Oct. 9 GOP*
MSNBC
1,081,000
342,000
Oct. 9 GOP*
CNBC
1,014,000
223,000
Aug. 7 Dems
MSNBC
893,000
297,000
*Nielsen allows NBC to combine the totals of these two airings (same debate) which would make 2,095,000 total viewers and 565,000 in the A25-54 demo.