John Diehl, the Republican chairman overseeing the St. Louis County Election Board, was trolling the Lincoln Day hospitality suites (snacking healthily on grapes and bottled water) when he recounted in detail how the county was the major power in Missouri’s Democratic presidential primary.

Diehl said he was shocked during the vote-counting Tuesday night when the Associated Press initially declared — while ballots were still being tabulated — that Sen. Hillary Clinton was going to win the Missouri Democratic primary, and defeat Sen. Barack Obama.

As we all know, that projection was wrong.

Diehl said he told the AP stringer camping out at the Election Board headquarters in Maplewood that the news service was making a big mistake, with so many county votes still uncounted — especially since Obama was carrying the county, and his margin was increasing as more votes were being tabulated.

Why was the spread increasing? Because the Election Board counted the votes by congressional district and the 1st Congressional District — with the county’s largest bloc of Democratic and minority votes — was counted last.

After AP “called the election” for Clinton, CNN called its stringer at the Election Board and asked her whether the network should do the same. She asked Diehl, who emphatically said No.

At the stringer’s request, Diehl got on the phone with the CNN representative, and explained about the vote count and Obama’s increasing edge.

“I told CNN that he was going to win, and carry the state by 8,000-10,000, votes,” Diehl said. “I was right.”

Where AP erred, he said, was in not checking in with him or other county election officials before making its decision.