Editor's note: CNN Contributor Bob Greene is a bestselling author whose books include "Late Edition: A Love Story" and "When We Get to Surf City: A Journey Through America in Pursuit of Rock and Roll, Friendship, and Dreams."
(CNN) -- We are now able to project a winner in the 2012 presidential race:
Brooks & Dunn.
If that wasn't clear enough already, it became abundantly so at the end of Newt Gingrich's victory speech in South Carolina last weekend.
As Gingrich left the stage, his campaign staff played a song through the speaker system.
The song was "Only in America," by the country duo Brooks & Dunn.
Of course. That song has become a bipartisan standard in recent presidential campaigns. George W. Bush and Dick Cheney used it at their rallies; Barack Obama used it at his rallies; John McCain used it at his rallies; and now Gingrich is using it. Mitt Romney, too.
Politicians have long utilized campaign songs, but it is unusual for Republicans and Democrats to share the same song. After Bill Clinton used Fleetwood Mac's "Don't Stop (Thinking About Tomorrow)" in his 1992 campaign, it would have been inconceivable for a Republican opponent to use it at GOP rallies that year, or for Republicans four years later to use it. It would have reminded potential voters of the other guy.
But "Only in America" has managed to transcend party lines; its lyrics, about the U.S. ideal of opportunity for all, seem to speak to a deeply held national belief, even a yearning, and the insistent opening guitar chords rivet an audience. "Only in America," Ronnie Dunn's voice sings, "Dreaming in red, white and blue; Only in America, Where we dream as big as we want to. ..."
When Obama, late in the summer of 2008, finished his speech accepting his party's nomination for president in that packed Invesco Field football stadium in Denver, there was the Brooks & Dunn song booming out of the speakers, becoming the soundtrack of the historic moment. That four years earlier the song had been playing at Bush/Cheney events didn't seem to matter. "We all get a chance, Everybody gets to dance. ..."
Brooks & Dunn, after a 20-year career of platinum albums and No. 1 hits, have broken up and no longer perform together. But last week I was able to get in touch with both Kix Brooks and Ronnie Dunn, and in separate conversations we talked about what having their song become the go-to anthem for presidential candidates means.
"The song was never intended to be partisan, and it isn't," said Dunn. He was in rehearsals for a solo tour in support of his new single, "Let the Cowboy Rock," and even though the Brooks & Dunn duo is no more, he said he often thinks about the political life that song of theirs has taken on.
"It's about the opportunity, in America, to try to attain anything you want," he said. When, in 2008, the song began to be heard at rallies for both sides (neither candidate had asked for their permission), he and Brooks made the decision not to say anything publicly about their private political preferences: "We kind of laid low. We did that on purpose."
Which made all kinds of sense. Some singers and bands, when their songs are played by candidates they don't favor, loudly demand that the candidate stop immediately. Dunn and his partner instinctively realized that if both parties had adopted "Only in America," they should just sit back and let their work be constantly heard by citizens of every political persuasion. When good fortune unexpectedly comes raining down on you, the last thing you want to do is reach for an umbrella.
"I'm moved by the whole thing," Dunn said. "Of all the voices in America, to have my voice be the one that sings those words . . . ."
Kix Brooks, who is completing his own solo album and also hosts the syndicated radio show "American Country Countdown," told me, "The song was never Republican or Democrat. I think that politicians of both parties get that."
Brooks wrote the song, in collaboration with Nashville songwriters Don Cook and Ronnie Rogers, as simply "an appreciation of our freedoms in America." When Brooks & Dunn were filling arenas and stadiums night after night, there would come a moment, midway through "Only in America," when local members of the military invited by the band -- usually four or five of them, from the different branches, always in uniform -- would march in crisp formation onto the stage, and would face the audience, then salute.
The audiences would stand and cheer, some people with tears flowing. It might be the one and only time in the lives of the young men and women from the Army, the Marines, the Navy and the Air Force when they would have a moment like this: when they would be onstage in front of tens of thousand of people, and be applauded with gratitude for the sacrifice they were making. "After the song," Brooks said, "the soldiers would leave the stage, and I would look at them, and they would just be glowing."
Campaign songs have always been a tradition with presidential candidates -- "Marching with McKinley" for William McKinley, "He's All Right" for Benjamin Harrison, "Get On a Raft with Taft" for William Howard Taft, "Keep Cool and Keep Coolidge" for Calvin Coolidge -- but only in recent years have songs that are already big hits, and that were not written for a candidate, been made a regular part of campaign playlists.
With the Brooks & Dunn song, neither political party seems to want to be the one not to play it. It has, without any push from the men who sang it, managed to become a part of the presidential process.
"If the candidates want our song to come out of their speakers, it's fine with me," said Brooks, who was born in Shreveport, Louisiana, during Dwight D. Eisenhower's first term.
"I just feel lucky. I never got tired of singing it" said Dunn, who was born in Coleman, Texas, also while Eisenhower was in the White House.
Only in America.
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The opinions expressed in this commentary are solely those of Bob Greene.