By Barb Shelly, Kansas City Star editorial page columnist

The ditch-Biden rumor won't go away.

This is the rumor that has Joe Biden dropping out so that Barack Obama can replace him with Hillary Clinton. Or maybe Kathleen Sebelius.

It pops up on blogs of all political stripes. Andrew Malcolm, a blogger for The Los Angeles Times, had a post on it today. A few days ago I saw Matt Lauer interviewing somebody about it on Today.

Enough! Obama has been campaigning for, like, forever. Long enough for us to see that mercurial moves are not his style. He picked Biden because of his foreign affairs credentials and his long record in the Senate. Everyone knew Biden was a wind bag when Obama selected him. His faux pas on the campaign trail are no surprise to anyone who's followed the U.S. Senator from Delaware. He's a walking gaffe machine, but no one in the know would ever call him vacuous, or uninformed, or anything less than knowledgeable.

Before the bloom faded away from GOP vice-presidential nominee Sarah Palin, the thinking in some quarters was the Obama made a mistake not selecting Clinton, and that maybe he should sacrifice Biden and correct the mistake.

Absolutely not. Hillary might bring some votes to the ticket, but she would want something for them. She'd want a steering wheel in the next administration, is what she'd want.

Obama knew he couldn't run an administration with Clinton in the arena. It's a credit to him that he passed her over. Governing is more important than politicking.

Biden was a good choice. And if a running mate takes a powder, I don't expect it to be him.