As the Democratic National Convention draws near, political observers are grasping at every possible piece of evidence in an effort to divine Sen. Barack Obama’s choice of a running mate. The announcement Wednesday that Gov. Kathleen Sebelius is scheduled to speak at the convention on Tuesday, Aug. 26, was taken by many as a sign she wouldn’t be the choice. The thinking is that being scheduled elsewhere on the program means Sebelius won’t fill the slot reserved for the vice presidential nominee on Wednesday, Aug. 27, but in a quick take Marc Ambinder of The Atlantic says it ain’t necessarily so, because the Obama campaign continues to insist the two issues are separate.¢¢¢On the other hand, Paul Murdock at Forbes.com still has Sebelius on the short list. Murdock updates the pros and cons of several possible veeps, including Sen. Joe Biden, who is rising to the top of some observers’ lists. Biden, he says, has strengths, but he’s also known as a loose cannon who might have trouble sticking to a campaign script. Murdock’s top four are Sebelius, Biden, Sen. Chris Dodd and Sen. Evan Bayh, but he also notes, “surprises are always possible.”¢¢¢In a column mostly written before Sebelius’ speaking slot was announced, Andrew Romano of Newsweek already had dismissed the possibility that she or Virginia Gov. Tim Kaine would be Obama’s choice. Obama must have someone with foreign policy credentials, Romano says. The top contenders that meet that qualification are: Biden, Sen. Chuck Hagel, Sen. Jack Reed and former Sen. Sam Nunn.