Objectively, the best should go to “Respect” (or “Penny Lane”, though there are enough Beatles songs on the lists that they can lose for a year). But I went with “Daydream Believer” - I’m a Monkees fan, and if memory serves, this is pretty much their last gasp as far as having #1 singles goes.
I hate Morrison, too, but grudgingly respect a lot of their songs for the reasons you describe. When I hear Break on Through, People are Strange, the longer Light My Fire - those are great songs, even if Jim is a douche.
I voted for Respect, with Penny Lane as a close second - if we could really include Strawberry Fields, there’d be no contest. Respect is an historic song - truly great, with a vocal that still sets the standard, and the power of being a touchpoint for the Women’s movement at the time…
Amazing to think that there is no Jimi Hendrix, Cream, etc. listed - let alone the Velvet Underground and Nico!!
“Penny Lane,” followed by “Billie Joe” and “Daydream Believer.”
I surprised myself and went with a personal favorite, the Turtles’ “Happy Together.”
As I’m sure you know, Hendrix made the Top 40 charts only once, with “All Along the Watchtower.” If you go with the strict definition of “One-Hit Wonder” (that is, an artist who placed only one song in the Billboard Top 40), then Hendrix was one.
Of course, these were the days when the divide between AM Top 40 and FM “Underground” rock was at its most pronounced, though there was some crossover.
Cream hit the Top 40 three times, with “Sunshine of Your Love,” “White Room” and “Crossroads.” In retrospect, it’s odd that perhaps their most commercial song, “Badge,” failed to dent the Top 40 (it only hit #60 in the US, though it was #18 in the UK).
Needless to say, The Velvet Underground never made it anywhere near the Top 40! Which is no comment on the excellence of their work…I love 'em.
For me, it boiled down to “Light My Fire” or “Respect”. I opted for Aretha over Jim.
As for the absence of the Velvet Underground and Nico, their first release in 1967 barely scraped the bottom half of the Billboard Top 200 Album chart before disappearing. Even free-form FM stations largely ignored it.
Light My Fire, and I agree completely with what others have said, specifically about Morrison. The Doors first album was an incredibly good album.
I wasn’t going to talk about this until a few polls from now when it becomes relevant, but you’ve twisted my arm. 
Originally, Billboard tracked A-sides and B-sides separately. A notable example of this occurred in 1956, when Elvis’ “Hound Dog” was released as the B-side of “Don’t Be Cruel” and both received significant airplay; because Hound Dog was the B-side, it stayed trapped at #2 while Don’t Be Cruel was the #1. In 1969, Billboard changed its policy due to the growing prevalence of popular B-sides and double A-sides, and decided that if both sides of a single, or both A-sides, were getting significant airplay, that they’d share the same spot on the chart. (When we get to that point, I’ve decided that I’ll list the two songs separately for voting.) That policy remained in effect until 1998, though it had mostly stopped being relevant by then due to the death of vinyl (there was one notable instance in 1997, though). In 1998, Billboard started tracking all songs released on an album regardless of whether they’d been issued as singles or not, rendering the issue moot.
Oh yeah, I know - just thinking about what hugely influential musicians were producing work that are reflected on the list of #1’s. It’s always true, even during these transformational years of the 60’s, but looking at the shadow cast by Hendrix, Cream and the Velvets…
To me, they are inseperable. That’s why I voted for Penny Lane (and Strawberry Fields).
A good year for songs. One of the best so far.
My picks:
Bobbie Gentry - “Ode To Billie Joe” (my vote)
The Beatles - “Penny Lane”
The Turtles - “Happy Together”
The Association - “Windy”
The Doors - “Light My Fire”
The Monkees - “Daydream Believer”
Can there be any choice other than “Respect”? Well, okay, yes, maybe “I’m a Believer”.
By the way, enjoy the embarrassment of riches that is the 1960s, as I’ve gone on ahead and looked at the yearly number one singles through 1979, and, well? There’s a reason so many people hate seventies music.
Had to choose “Respect,” which I think to this point is easily the most impressive vocal performance of any song I’ve voted for in this series.
The Letter got my vote for this year. Too bad we won’t see The Box Tops in the 1968 poll. Their excellent Cry Like a Baby only made it to #2.
I made this exact same comment in the 1966 #1 singles poll.
Incidentally, in terms of good number one singles, the 80s aren’t much better – and I’m not saying that as some bitter old baby-boomer who thinks music’s gone to hell since 1969. The 80s were when I was a teenager/young adult and even then I was often annoyed by the drivel that often made it to the top of the charts.
I do not think this year is a strong as the previous two, but still many good choices. Although “Respect” and “Light My Fire” are very strong singles for their respective singers, I went with a personal favorite, “The Letter”. Alex Chilton is too often forgotten in music history.
Give me a ticket for an aer-o-plane…
The 2000s decade was also pretty bleak for #1 singles, up until the dawn of the Kesha Era in 2009. Music has never been better.
You are only looking at the songs that made it to number one on the (mostly AM) radio charts. The 70’s had some of the best music ever, but it was being played on “underground” FM stations. Here’s a list of great 70’s rock that didn’t make the Billboard charts (not that anyone cared).
There really ought to be two categories for these, as in best soul and best rock/pop. Aretha took this year in a walk, but The Doors really slammed in with a moody number (unlike the next year with their horrid “Hello, I Love You”). I’m going with “Light My Fire”, as it was an album I played over and over again during my year in 'Nam.