John McCain didn't win the Republican nomination by uniting Republicans, but rather simply by being the Last Sane Republican Standing after Rudy Giuliani and Mitt Romney humiliated themselves.

So it comes as little surprise that after three months of trying to "unite" the GOP, the ideological divisions are only growing worse.

On May 6, nearly 1/4 of Republicans in Indiana and North Carolina voted for Mike Huckabee, Ron Paul, Mitt Romney, or "other."

Ron Paul remains in the GOP primary race, and may support the Libertarian candidate if he gets snubbed at the Republican convention. (Paul gained national fame as the Libertarian candidate for President in 1988, and spoke at the Libertarian convention in 2004.)

The Libertarians just got a credible candidate, former Rep. Bob Barr (R-GA), who has been a strong critic of Bush's dictatorial policies. Barr's candidacy is freaking out Sean Hannity because Barr could be a "spoiler" like Ralph Nader in 2000.

And to make matters worse, hard core Republican Theocrats want to see McCain lose so they can run Mike Huckabee against President Obama in 2012. As Robert Novak writes, those Theocrats even see a Divine Plan:

One experienced, credible activist in Christian politics who would not let his name be used told me that Huckabee, in personal conversation with him, had embraced the concept that an Obama presidency might be what the American people deserve. That fits what has largely been a fringe position among evangelicals: that the pain of an Obama presidency is in keeping with the Bible's prophecy.

According to this activist, at the heart of the let-Obama-win movement is longtime Virginia conservative leader Michael Farris -- the nation's leading home-school advocate, who is now chancellor of Patrick Henry College (in Purcellville, Va.) for home-schooled students. Best known politically as the losing Republican candidate for lieutenant governor of Virginia in 1993, Farris is regarded as one of the hardest-edged Christian politicians. He is reported in evangelical circles to promote the biblical justification for an Obama plague-like presidency.

So with all that anger on the Republican Right, McCain is still campaigning all the way to the right, rather than moving to the center. In fact McCain is now flip-flopping on his "rape, incest, and life of the mother" exception to his plan to outlaw abortions.

In the 2000 primaries, McCain attacked George Bush for embracing the GOP platform, which has no exceptions, and the debate video is crystal clear. But now McCain himself is embracing that same GOP platform, and alienating the moderate Republican women who made him the GOP nominee:

“If he doesn’t change the platform, then he’s being the same kind of hypocrite that he accused Bush of being in 2000,” said Jennifer Blei Stockman, the co-chairwoman of Republican Majority for Choice. “To not accept abortion in cases of rape and incest, give me a break. That’s sick. That’s inhumane.”

Now that she mentions it, that's not a bad bumper sticker: 

Sick. Inhumane. John McCain.

Update 1: The ABC/WaPo poll quantifies GOP dissatisfaction with McCain:

relatively few mainstream Democrats (as opposed to independents) say they'd cross over (13 and 10 percent, respectively [Clinton/Obama supporters]). And as many Republicans say they'd defect the other way - 10 percent for Clinton if she faced McCain; 15 percent for Obama vs. McCain.

Democratic division is now at its peak and will mostly disappear after the convention. Republican division is likely to increase over time as McCain gets more "vetting" from the Corporate Media and makes a lose-lose choice between the right and the center in his VP pick.