Christopher Cross - "Sailing" (1980)
Despite the frequency of D in the bass, I hear A as tonic here. The pitch material is limited to an A major diatonic collection with the exception of the instrumental bridge from 2:43-3:08. It is not a surprise when the song concludes on a D (IV) chord (E is added to the triad), as each previous chorus ends this way (1:47, 2:37). Still, the resolution feels less complete than it would had a I chord been placed at the end. (This is, of course, not a bad thing and makes perfect sense given the lyrical content.)
Starship - "We Built This City" (1985)
F is the tonic pitch here, though as in Cross' "Sailing," each chorus ends on IV (Bb here). This emphasis prepares the listener for the use of Bb as a pedal during the outro beginning at 4:24. Also like "Sailing," chromaticism is used sparingly. Here it is mainly reserved for the third and fourth line of the verse, where the harmony is Eb/F | C/F | F | (as in 0:37-0:42).
Green Day - "When I Come Around" (1994)
I'll go with F# as tonic here, with the chord progression I-V-vi-IV cycling through most of the song. 0:54-1:02 and 1:53-2:02 present a repeated II-IV pattern (yes, that's major II) concluding with a B major chord that supports a C# in the lead vocal (IVadd9). Following several repetitions of the titular line from 2:31-2:48, the song ends on IV at the conclusion of the I-V-vi-IV pattern.
Faith Hill - "Breathe" (1999)
Here the beginning of the verse contains the chords Am, G/B and Cadd9. The initial absence of F(#) allows either G or C to be heard as tonic, though for me, the vocal's emphasis on G suggests the former interpretation. This ambiguity is removed at 0:46, as a D major (G: V) harmony is introduced. Another D (V) chord at 1:14 leads directly into the chorus, which begins with a repeated G: I-ii7-IV(add9)-V(sus4). The song ends with the opening lines of text repeated against the same harmonic pattern concluding on C major (IV), with B and D added.
Michelle Branch - "All You Wanted" (2001)
Though an F in the bass begins the introduction as well as every verse and chorus, Ab is clearly tonic here. The verse employs Ab and Eb pedals above the bass pattern F-Eb-Db-Ab (scale degrees 6-5-4-1), and the chorus uses the (slightly) more tightly structured harmonic sequence Ab: vi7-IV(add9)-I-V. A V chord, initially appearing in first inversion at 0:30, serves to connect various sections. (The use of V6 at 2:20 is rather memorable, as scale degree 7 is briefly present in both bass and Branch's lead vocal.) The song ends with the repetition of an earlier line of text (from 1:32-1:42) and a IV chord (Db major, with Eb added).
Kesha - "Tik Tok" (2009)
I hear D as tonic throughout, with the bassline Bb-C-D first harmonized in thirds (with the melodic line D-E-F) during the verse, and later supporting complete triads in the chorus. This progression, Bb major-C major-D minor, can be represented by d: VI-VII-i. G minor (iv) appears occasionally in the verse (as in 0:31-0:33), chorus (as in 1:03-1:05) and bridge (as in 2:14-2:15) as well. The song ends abruptly with a single Bb in the bass following the final chorus, as if beginning another refrain.
Miley Cyrus - "Wrecking Ball" (2013)
As in "Tik Tok," I hear D as tonic throughout, though the chorus (as in 0:40-1:02) may be heard as promoting F or Bb as tonic. The music from 2:38-2:42 (toward the end of the bridge) presents d: V4-3 (A major) and contributes to the case for hearing D as tonic. Each chorus ends on Bb major (d: VI) with Cyrus' vocal on the note Bb. This same configuration ends the song, completing the last of several repetitions of the chorus' final lyric (beginning at 3:23).
Adele - "Set Fire to the Rain" (2011)
D is immediately established as tonic with the progression d: i-III-VII-iv in the introduction and verse. The chorus is also centered on D and presents d: i-VII-iv-i-VII. The song ends with d: VI-VII, a motion first introduced at 2:22-2:26. Against the C major chord at 3:53-3:58, the vocal falls from G to F as if anticipating a tonic (D minor) triad that does not arrive.
John Legend - "All of Me" (2013)
Though the beginning of the chorus (as in 1:00-1:31) is centered on Ab [Ab: I-vi-ii6-V(9-8,4-3)], I hear F as tonic overall. The verse (as in 0:16-0:31) and the end of the chorus (as in 1:31-1:46) contain f: i-VI-III-VII (the introduction contains the same harmonic pattern with i and VII missing chordal thirds). The song ends with a repetition of the last portion of the chorus (4:18-4:35), closing on an Eb major (VII) chord.
Kelly Clarkson - "Stronger (What Doesn't Kill You)" (2011)
The tonic here is A, and with the exception of the bridge (2:15-2:37), the harmony consists of a repeated a: i-VI-III-VII6. Clarkson's vocals exit at 3:31 and the song ends with a final repetition of this harmonic pattern, closing on G/B (VII6). Worth mentioning is the Bb major chord (bII) during 2:19-2:23 and its subsequent direct return to the tonic (A minor).
Weezer - "Buddy Holly" (1994)
I hear Ab as tonic here, though F minor begins each verse. The chorus (as in 0:28-0:43) presents Ab: I-IV-V-I-IV-V-vi-IV-V-I-IV-V-I. After three repetitions of the final line of the chorus (2:26-2:36), the harmony makes a quick move to F minor (vi) to end the song.
Bonnie Raitt - "I Can't Make You Love Me" (1991)
Despite the frequency of Eb major and G minor chords, I hear Bb as tonic here. Simplified (chordal sevenths and ninths, most often the notes Bb and F, are frequently added), the chords in the verse (as in 0:32-1:11) are Bb: IV-vi-IV-I6-vi-ii[-V(6-5,4-3)]. The chorus (as in 1:13-2:15) presents Bb: IV-I-IV-I(6)-IV-vi-IV-V6-vi-IV-V6-vi-ii-V-IV-I-IV-vi-IV-I6(-vi)-ii. The first chorus leads seamlessly into the second verse beginning at 2:16; the second chorus leads to an extended outro beginning at 4:00. At 5:13, the song seems to have reached an end on Eb major (IV), but moves unexpectedly to Ab major (bVII) at 5:21.