Since we ran with the speculation du jour for the Republican running-mate choice, why not round it out with the hottest rumor on the Democratic side, too?  And like the Republicans, hot doesn’t necessarily connote surprise.  Tim Kaine has garnered today’s big buzz, but it’s not like he’s been overlooked in the past.  The Washington Post and Politico both restart the Kaine Scrutiny:

Virginia governor Tim Kaine has told close associates that he has had “very serious” conversations with Sen. Barack Obama about joining the Democratic ticket and has provided documents to the campaign as it combs through his background, according to several sources close to Kaine. …

But several people who have spoken to Kaine directly said he has talked about the seriousness of the possibility. All requested anonymity, citing the campaign’s desire to keep the process secret. One said Kaine has stressed that there are other top candidates but described his discussions with Obama’s campaign as “very serious.”

Two other associates said Kaine’s staff is heavily engaged in providing the background research necessary to allow Obama’s campaign to search for potential political land mines. One source said Kaine chief counsel Larry Roberts is coordinating with Obama’s team. Roberts cold not be reached for comment. Kaine will be in Washington today for his monthly interview on WTOP.

Since campaigning together during Kaine’s 2005 gubernatorial race, he and Obama have become friends. Kaine, who like Obama has Kansas roots, has returned the favor, campaigning across the country for Obama during the primaries. In recent weeks, Kaine and his staff have been in frequent contact with Obama and the presidential campaign about strategy and operations in Virginia and elsewhere. Kaine has said he plans to attend the Democratic convention in Denver with his wife and children.

Kaine fits a couple of criteria for Obama.  First, he’s an outsider, and Obama says he wants someone who can credibly join in his mission of changing the way Washington operates.  That almost explicitly rules out Hillary Clinton, Chris Dodd, and Joe Biden, and probably even Evan Bayh to some extent.  Second, it puts someone with executive experience on the ticket.  Maybe most importantly, it puts Virginia into play for the Democrats, who need to turn a significant red state blue — and Virginia is probably the most likely to switch.

On the other hand, Kaine has some serious drawbacks.  Other than being Governor for three years, Kaine doesn’t have much on the resumé.  He has no foreign-policy experience, and no military experience, either.  And as the Post mentions in its profile, Kaine hasn’t exactly set the world on fire in Virginia.  Three years without any significant accomplishments will not generate excitement for this running mate, and then there’s the inconvenient matter of the budget deficit that has appeared in Virginia on Kaine’s watch.

Democrats thought enough of Kaine to have him deliver the Democratic response to the State of the Union speech in 2006, and he didn’t do too badly, but he didn’t shine either, thanks in part to the lackluster material.   They haven’t had him do much nationally since then.  One has to wonder whether Kaine has the substance it would take to bolster Obama — or whether his lack of substance might not appeal to those on Team Obama who worry about getting overshadowed by the running mate.