Wednesday's season-opening show was watched by about 18 million viewers and expectations were that that number wouldn't drop much Thursday night.
"Afterward, Keith (Urban) told me he liked my song and he would buy my record," Luning said. "That was pretty cool.
"The entire process was kind of a blur," he admitted. "I mean auditioning in front of three superstars like that ... it was really, really cool."
After getting the judges' approval, he did the obligatory walk off the set and into the jubilant arms of mom Kathy, dad Michael and aunt Paulette Luning.
And the show, which was taped last fall, happened to air on David's 27th birthday.
He has now passed three enormous hurdles in the Idol journey.
Luning, who performs frequently around Sonoma County, went to last summer's tryout at AT-T Park in San Francisco ("I got there at 4 a.m. that day and it was cold. I was way out in the outfield when I performed," he recalled), was called back for a second tryout a month later and then was picked for Thursday's show.
At the seven audition sites scattered around the country, 72,000 singers tried out and there were 212 subsequent Golden Tickets awarded.
Luning has one of those.
Now what happens as Idol weaves its way to a May 21st finale at New York City's Madison Square Garden for the first time?
Since much of that already has been recorded, Luning can't say, but the show turns live when it reaches the Hollywood stage. In the past, there have been elimination rounds in Las Vegas and Los Angeles before that round, but that may have changed this year.
According to TV Guide, in December judges and contestants were reunited at Santa Monica Airport's Barker Hanger, where they faced a surprise round of eliminations. The round apparently was added as a make-over for the middle episodes, which typically have been the lowest rated.
"In this first portion, the contestants have actually gotten better as a whole and there is less crumbling," Idol host Ryan Seacrest told TV Guide. "They've been more impressive than we thought when we first met them."
Luning, who was born in Santa Rosa, moved on to Cotati, then Camp Meeker and finally Forestville. After finishing at Summerfield Waldorf in 2005, he spent a couple of years at UC Santa Cruz before moving on to the Berklee College of Music in Boston.
"I majored in music and electronic film scoring at Berklee for a couple years," he said. His career path then swerved to "Americana" music.
"It's like Mumford and Sons," said the accomplished acoustic guitar, harmonica and bass player. "Folk, rock, country."
So, how did the Idol journey start in the first place? "I hadn't even thought about it," he admitted, "but my mom kept encouraging me to try out. I'm glad she did. It's a great way to get your music out there."
(You can visit Luning's website at <a href="http://davidluning.com" target="_blank">davidluning.com</a> and follow "American Idol" with daily updates on <a href="http://idol.blogs.pressdemocrat.com/" target="_blank">Bill Pinella's Idol Chatter blog</a>.)