The song's sunny lyric develops what Rolling Stone called "a rare and timely moment of unabashed optimism" for Springsteen, possibly connected to the impending arrival of the Barack Obama administration:

The title phrase is present in both the verses and chorus, and occurs some twenty times altogether in the song. The arrangement is mid-tempo, propelled by an acoustic guitar with organ and electric guitar washes throughout; the glossy Brendan O'Brien production also features partly submerged "la-la" backing vocals. The instrumental break features Springsteen whistling against a bari sax line.

"Working on a Dream" was first performed during Springsteen's November 2, 2008 appearance in Cleveland for Barack Obama's 2008 presidential campaign, in an acoustic performance accompanied by Patti Scialfa. A chopped-up airing of the recorded version first appeared during the November 16 NBC Sunday Night Football broadcast at halftime.

The intact "Working on a Dream" began airing on radio stations and their websites on November 21, 2008, and was made available for free download via iTunes and the Sony BMG website on November 24. The track entered the UK Singles Chart at position 195 the following week. A music video appeared on some foreign sites showing the recording of the song. The song was a big hit on the American Triple-A Charts, peaking at No. 2, blocked only by "Get On Your Boots" by U2.

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Wikipedia