Fox has made it 16 consecutive Tuesday ratings victories, last night riding more powerful perfs by “American Idol” and “House,” according to preliminary nationals from Nielsen. NBC also did well in the evening’s final hour with “Law & Order: Special Victims Unit.”

At 8 opposite all firstrun sweeps fare, “American Idol” (9.7 rating/27 share in adults 18-49, 23.8 million viewers overall) dominated but was down a bit week-to-week. “House” then impressed at 9 (7/17 in 18-49, 17.3 million viewers overall), ruling its hour despite extra drama competition from the first hour of a two-hour “Law & Order: SVU” event (4.2/10 in 18-49, 13.6 million viewers overall).

For NBC, the conclusion of the “SVU” event, featuring characters from Friday series “Law & Order: Trial by Jury,” easily won the 10 o’clock hour (6.3/16 in 18-49, 18.7 million viewers overall), besting the combined drama deliveries of CBS’ “Judging Amy” (3/8 in 18-49, 10.8 million viewers overall) and ABC’s “Blind Justice” (2.4/6 in 18-49, 6.4 million viewers overall).

CBS ran second every hour on the night, led by the penultimate episode of “Amazing Race 7” (5.1/12 in 18-49, 13 million viewers overall). At 8, “NCIS” averaged a 3/8 in 18-49 and about 13 million viewers overall.

ABC had a sluggish night, led by “According to Jim” at 9 (3.2/8 in 18-49, 8.5 million viewers overall).

Preliminary 18-49 averages for the night: Fox, 8.4/22; NBC, 4.1/11; CBS, 3.7/10; ABC, 2.5/6; WB, 2.2/6; UPN, 1/3.

In total viewers: Fox, 20.5 million; NBC, 12.6 million; CBS, 12.3 million; ABC, 6.8 million; WB, 5.1 million; UPN, 2.5 million.