I don’t know about you, but my head is spinning with all the theories out there about who will win this presidential election and why.

I’m as guilty of promulgating them as anyone. Ask any political consultant for a prediction on a race — on anything really — and we’ll take you on a trip around the world. We’re worse than the commentators before an NFL game:

“I’ll tell you, Steve, no lefthanded president who has lost the Methodist vote in Wisconsin has ever been re-elected in a year that ends with the number two…”

This is my firm and final theory then — it is also my first incidentally — on why I think Mitt Romney will be the next president of the United States:

Romney will win because Barack Obama has not done a good enough job.

That’s it.

Call it the Obama-Occam’s Razor Theory if you want to dress it up — the simplest explanation is usually the right one — or the Homer Simpson “D’oh!” Theory, which I much prefer. But either way, the result on Nov. 6 should be predictable. Most Americans think the country is in trouble and headed more deeply into it rather than out of it, so come Election Day they will replace the current White House occupant with the well-qualified challenger.

Clint Eastwood said this best at the Republican National Convention in Tampa (when he wasn’t talking to the chair):

“Politicians are employees of ours,” the “Unforgiven” actor and director said. “And when somebody does not do the job, we got to let ’em go.”

I was next to the convention stage with a colleague when Eastwood said that, and the simple truth of his words was palpable. “That’s the whole election,” I whispered to her beneath the roar of a partisan crowd.

And it is.

The rest of this column is available at Newsday and Newsday Westchester.  Thanks for reading!