President Bush most likely had his most-watched State of the Union address in several years last night, though he owes some of that to Fox’s warbling “American Idol” wannabes.

The Big Four networks combined for 31.4 million total viewers during the two-hour presidential address and Democratic rebuttal last night, 14 percent better than the 27.6 million they averaged last year during the same 9-11 p.m. slot.

That’s according to Nielsen overnight figures, which measure time period and not program data; some of the networks moved to non-political programming after 10:30 p.m. Nielsen will issue numbers later today that break down the numbers by timeslot and include cable and Spanish-language network ratings, which will give a more complete picture of the real numbers.

For the third straight year, Fox led among total viewers for the SotU as fans stuck around after the 8 p.m. episode of “American Idol.” Fox averaged 10.5 million viewers from 9 p.m. to 11 p.m., up 24 percent over last year’s average.

NBC was second with 7.5 million, followed by CBS at 7 million and ABC at 6.3 million. The Big Four combined for a 10.3 adults 18-49 rating for the speech, which was 2.3 points lower than Fox’s “Idol” averaged to open the night.

The increased tune-in was due in part to “Idol” but likely also to the president’s recent decision to send more troops to Iraq, a decision that has polarized Washington and sparked debate throughout the country. The recently launched presidential campaigns of prominent Democrats Hillary Clinton and Barack Obama also likely sparked more to tune in to see their reaction to the speech.

“Idol” had a slightly bigger audience than last year’s SotU night performance, though last year the SotU aired one week later. “Idol” averaged 31.2 million total viewers, 3 percent better than last year, and a 12.6 in 18-49s, 2 percent better than last year.

But the third episode of the hit reality show was down from last year’s third episode, a two-hour show that averaged 34.8 million total viewers and a 15.0 rating. The downturn may have been because of the SotU or the shorter length of the show, but it’s an interesting development after last week’s monster premiere.

“Idol” led Fox to a first-place finish among 18-49s with a 6.5 average rating and a 17 share. CBS was second for the night at 2.3/6, NBC third at 2.2/6, Univision fourth at 1.8/5, ABC fifth at 1.7/4 and CW sixth at 1.4/4.
 
At 8 p.m. Fox led comfortably with a 12.6 rating for “Idol.” CBS was second with a 3.3 for “NCIS,” Univision third with a 2.1 for “La Fea Mas Bella” and NBC third with a 1.8 for “Dateline.” CW was fifth that hour with a 1.7 for “Gilmore Girls” and ABC sixth with a 1.4 for a repeat of “America’s Funniest Home Videos.”
 
All of those networks except CW aired Bush’s speech during the 9 p.m. hour, with Fox first with a 4.3 rating, NBC second at 2.6, ABC and CBS tied for third at 2.1 and Univision fifth at 1.9. CW was sixth that hour with a 1.5 for “Veronica Mars.”
 
At 10 p.m. NBC led with a 2.1 average for State of the Union coverage and a repeat of “The Office,” with ABC second with a 1.6 for a whole hour of State of the Union banter. CBS was third with a 1.5 average for State of the Union and a “Two and a Half Men” rerun and Univision was fourth with a 1.4 for “Mundo de Fieras.”
 
Among households, Fox led the night with a 9.4 average rating and a 15 share. CBS was second at 6.2/10, NBC third at 4.8/7, ABC fourth at 3.9/6, Univision fifth at 2.3/4 and CW sixth at 2.2/3.