It’s over. Barack Obama is essentially the nominee. By every metric, Barack Obama is ahead. Whether you count total delegates, pledged delegates, or popular vote, Barack Obama has an insurmountable lead. He has this lead even if you count Michigan and Florida, which had their delegates stripped due to breaking party rules. The Clintons have no more trump card.

It’s not impossible for her to win, just incredibly unlikely. Let’s make a football analogy. It’s first and 10, there’s less than 2 minutes on the clock. All Obama has to do is take a knee. He doesn’t even have to play defense anymore. And even if he fumbles it away, she has to get a field goal, retrieve the onside kick, and score a touchdown. It’s over.

Obama has essentially been running out the clock. As more and more delegates were dealt either way, Obama retained his lead. Clinton never made a significant dent. At some point, one runs out of time to regain the lead. Clinton has run out of time. There aren’t enough delegates left.

This is true even when you factor in superdelegates. By the end of the process, even you give Clinton a generous number of pledged delegates, she’ll need to convince over two-thirds of the remaining superdelegates to overturn the will of the people. If you give her a generous number of Florida and Michigan delegates, the number decreases, but she still has to convince more than a majority of superdelegates to switch sides.

It’s not only a tall order; it’s essentially impossible. Many superdelegates have already said they’ll vote for the candidate who won the most pledged delegates. Psychologically, the superdelegates are afraid of backlash and afraid of turning away a generation of energized voters.

Clinton started out with a 100 superdelegate lead on Obama, and now they’re essentially tied. Just today, Obama picked up 3 superdelegates and a Clinton superdelegate defected. Clinton picked up one. Clinton has 271 superdelegates; Obama has 261 superdelegates. That’s over 500 delegates who have picked one side or the other. There’s less than 800 superdelegates total. There are less and less superdelegates to convince, and they’ve all been coming to the Obama camp. I don’t know of any defections the other way around.

She can’t win.

That being said, I think Clinton should stay. If she stays in the race without launching super negative attacks, then I think it’s good that she stays in. She looks as if she’ll win Kentucky and West Virginia. It’ll look really bad if Obama loses those states running against no one. Obama will win in Oregon on May 20, achieve a majority of pledged delegates, and then a wave of superdelegates will switch. She should still stay in longer and make Obama’s final June 3 victories more meaningful.

Why should we continue with these beauty contests? Because they have real consequences. The primaries and caucuses have seen record turnouts in many states. We want more Democrats registered to vote in the primaries. When they vote in a primary, they’re more likely to vote in the general. Voter turnout will be key to defeating McCain.

If Clinton refrains from personal negative attacks, this will be a net positive for the Democrats. The convention is not until August, and we will see a huge post-convention bounce for Obama. Don’t listen to the polls saying Clinton or Obama voters will switch to McCain. They won’t. These polls are as useless as those saying Rudy Giuliani was the man to beat — mind you, Giuliani did not win a single primary or caucus. It’s way too early to judge that (and if you want, I’ll pull out my knowledge of cognitive science to prove it). When Democratic primary voters look at the war, the economy, and health care, they’ll know that they prefer Obama. No matter how you spin it, record turnout for Democratic primaries is not going to help McCain.

Let Clinton finish the game. Maybe I’m giving the Clintons too much credit, but I think they can do it with dignity. I think going to the end, and getting Michigan and Florida seated, will reduce any bitterness. Forcing her out may engender too many hurt feelings, but leaving her in can mean more new Democratic voters.

Again, this assumes Clinton runs a decent campaign here on out. If she doesn’t, the superdelegates should force her out.