At a press conference Thursday, Hillary Clinton was asked about a report that she had tried to dissuade Bill Richardson from endorsing Barack Obama by saying, "He cannot win, Bill. He cannot win."

According to ABC News' Political Radar blog, Clinton denied she had said this, telling reporters, "That's a no... We have been going back and forth in this campaign of who said what to whom and let me say this, that I don't talk about private conversations but I have consistently made the case that I can win."

If Clinton were indeed making the latter case, it wouldn't be surprising. Both Democratic campaigns have made electability a hallmark of their messaging, and we already knew, among other things, that the Clinton campaign is going to superdelegates and discussing the Rev. Jeremiah Wright, Obama's former pastor, as an example of a potential weakness for Obama in a race against John McCain.

ABC, which was the first to have the story of the alleged conversation between Clinton and Richardson, also has a source telling them what we posted about earlier, that someone close to Clinton told Time's Mark Halperin it was Richardson who'd said Obama could not win. From ABC's reporting, it looks as if two separate alleged conversations are at issue -- one when Clinton tried to talk Richardson out of endorsing Obama, and one when Richardson supposedly told the Clintons he would not endorse Obama.

"A source with direct knowledge of Richardson's conversations with the Clintons added an intriguing wrinkle," Political Radar says. "Richardson himself told Sen. Clinton and former President Clinton that he didn't think Obama could win, back when he was (according to the Clintons) telling them earlier this year that he wouldn't endorse Obama."