In the end, it wasn’t North Carolina that made it clear that Hillary Clinton had no chance to win the nomination, but the nail-biter in Indiana. Barack Obama had been widely expected to win North Carolina, at one time by as much as 20 points, but Indiana’s demographics matched up with Pennsylvania and Ohio. When Indiana came down to 22,000 votes and a vigil over Gary and Lake County, the race was over. The only question will be when she admits it:

The twin results solidified the status quo in the Democratic race, one that now gives Obama the clear advantage in the battle for the nomination because of his solid lead in the tally of pledged delegates. Despite her Indiana victory, Clinton emerged even more the underdog in the nomination battle.

The results meant the senator from Illinois would to add both to his pledged-delegate margin and his lead in the popular vote, leaving Clinton with an even more daunting challenge in trying to deny Obama the nomination.

Although she managed to squeeze out a victory in Indiana, the night produced a far different outcome than the Clinton campaign had hoped for. In the closing hours of the campaigns in the two states, her advisers expressed confidence that she was gaining ground on Obama in North Carolina rapidly enough to hold his anticipated victory margin to single digits. They also thought she was positioned for a solid victory in Indiana.

Instead, Obama won North Carolina by 56 percent to 42 percent, and his popular-vote margin there — about 230,000 votes — wiped out the gains Clinton had made with her decisive victory in Pennsylvania two weeks ago. In Indiana, Clinton won by 51 percent to 49 percent.

Barack Obama now leads in pledged delegates, states, and has what looks to be an insurmountable popular-vote lead. Hillary has lost just about every argument that would convince superdelegates to switch to her side, and with nothing but smaller contests ahead of her, she doesn’t have enough potential over the next four weeks to reverse it. Even the electability argument disappeared with her momentum; if she couldn’t win Indiana convincingly, then she doesn’t have any special edge in electability.

Truthfully, Hillary has been a long shot since the first Super Tuesday defeats made Obama the front-runner. Operation Chaos may have helped her to remain in the race, and her predicament certainly made her a better candidate over the last few weeks, but her strategy always relied on convincing superdelegates to dump Obama. His unexpectedly strong showing in Indiana will convince them to stick with the frontrunner.

So how long will it take? Will Hillary really go all the way to Denver before surrendering? I’d guess that they will contest the last few primaries remaining. Kirsten Powers made a good point last night on Fox when she suggested that Hillary sees herself as a safety net — ready to take over if Obama has a “catastrophe” on the campaign trail. It would have to be at least an order of magnitude worse than Jeremiah Wright to knock him off the ticket now, but Hillary may be resting her ambitions on such slender reeds, and she doesn’t lose anything but time and money running out the string now.

Hillary won’t leave until the last primary contest closes its polls.