While Wallace was running for president in 1968, I heard him speak in Pensacola, Florida. That phrase is the one quote I distinctly remember from his speech. Concerning the Democrats and Republicans, I agreed with him then, and I agree with him now. I also agree with your "not a penny's worth of difference now."
They both support:
(1) aggrandizing the socialist U. S. Education Department;
(2) the United States protecting, supporting and bringing to power Muslim terrorists and drug-runners in Kosovo;
(3) building-up the Vietnamese and Chinese Communists;
(4) the abandonment and betrayal of American fighting men from WWII, the Cold War, the Korean War, and the Vietnam War;
(5) the Clinton/Bush immigration policies which have put our country at risk;
(6) the OKC cover-up;
(7) the TWA 800 cover-up;
(8) the degrading of American sovereignty;
(9) the meek acceptance of widespread FBI criminality, incompetence and arrogance; and (10) countless other evil actions of the same ilk.
On the other hand, the differences are "great." One will support more money for pre-school programs, the other won't. And let us never forget that one will support a larger tax break - that makes everything else acceptable to about one-half of the voters. The other half are paid-off with Government largesse.