Hagar the Horrible: The poor man’s Asterix & Obelix.
Except have decent looking uniforms. 
Since when did we have decent looking uniforms in the Air Force? Especially now that the BDUs are gone. 
Josh Brolin, the poor man’s Pierce Brosnan.
Hard work, dedication, and intelligence: The poor man’s nepotism
Goober and the Ghost Chasers and Funky Phantom: The poor man’s Scooby-Doo (although I did like Funky Phantom’s theme song.)
The Partridge Family is the poor man’s Brady Bunch
Barney is the poor man’s Big Bird
The Great Space Coaster is the poor man’s Sesame Street
Harry is the poor man’s Cookie Monster
Catnip and Herman is the poor man’s Tom and Jerry
Thriller is the poor man’s Twilight Zone
Good Times is the poor man’s Jefferson’s
Roseanne is the poor man’s Cosby Show
Maude is the poor man’s All in the Family
Friday’s is the poor man’s Saturday Night Live
Pan Am is the poor man’s Mad Men
When I was growing up, the poor man’s Sesame Street was Carrascolendas.
Elmo is the three year old’s Grover.
Ted from How I Met Your Mother is the poor man’s Ross from Friends.
Tax returns, the poor man’s savings account.
With apologies if it’s been mentioned and I missed it, I was reminded the other day that Jeff Kober is the poor man’s Willem Dafoe.
Savings account, the poor man’s stock market.
Peter Murphy, the poor man’s David Bowie.
The Huffington Post is the poor man’s Salon.
This was only relevant 15 to 20 years ago, but Jerry Doyle (on Babylon 5) use to make me think of Bruce Willis.
Arial, the poor man’s Helvetica.
Jesse Eisenberg, the poor man’s Michael Cera.
Michael Cera, the poor man’s Jesse Eisenberg.
…, the poor man’s _____________.
I’m years late, but this is exactly the first thing that popped into my mind upon reading the thread title.
Haven’t read the whole thread but…
Clarke Peters, the poor man’s Morgan Freeman.