Hillaryis44.org - I am going to ask you to do something you won't like. It's not going to be comfortable - and I can understand why you won't want to do it.  I ask that you step back and attempt to separate your emotions from your impulse reactions.
First, here are a few points where we can both agree:
1)  The Bush administration has left a stain of blood and shame on this nation - and it will take a LOT of time and tireless work by true patriots to wipe that stain from our nation.
2)  That both Barack Obama and Hillary Clinton are good people who share similar ideals and morals, and despite their differences it is clear that they both want what is best for our nation.
3)  That no matter how much you want to avoid it - a political campaign is a dirty business.  The Obama supporters believe with all their hearts that they were the ones wronged by Hillary and her supporters.  As you well know, the Hillary supporters believe exactly the opposite.  Both sides believe it totally and completely, and can't understand how it could be viewed any other way.  How can that be?  There are only one set of facts - how can they be interpreted so very differently by two groups?  Obviously - because the prize is so great - and the candidates are both such good motivators that they have convinced us that every attack does not only impact the candidate - it impacts you and I as well.  We feel it no differently than a physical punch to the gut.  This is not true of the passive observer of this race (like my wife - who can't understand why I get so passionate and fired up) - but it does effect a good number of the vocal supporters like you and I. 
I was an ardent supporter of Hillary for President from the time she left the White House.   Her handling of the many controversies present during Bill's Presidency (whether they were real or made up by the wacko right wing) is something that has inspired millions of people.  She was railroaded by the criminally negligent right wing congress when she attempted to help out our Country and join the rest of the civilized world with a form of socialized healthcare.  She is a great woman, a role model, and a patriot.
But she's also made her mistakes.  I'm not going to list them here because this is not about criticism of her - but instead an appeal to her most vocal supporters who are threatening to do the unthinkable - to vote to continue the atrocities of the Bush Administration for another four years.
I have supported Senator Clinton for 8 years and donated to her Senatorial Campaign.  I personally believe she would have been President if she'd run in 2004 (I understood why she couldn't).  I was intrigued by the  Obama Nation although I admired the enthusiasm he was generating, but I stuck with my candidate.  
But I also committed to fall in line with my party once a nominee was selected (unless it was Mike Gravel - because I believe that would be one of the prophesies signaling the forthcoming apocolipse).  I was a Human being first, American second, Democrat third - and Hillary supporter fourth.  I couldn't imagine four or eight more years of Republican rule - especially with the near dictatorial powers the Bush administration bestowed upon themselves and on the office.  I couldn't stand any more torture, rendition, war, greed, corruption, rape of the constitution, murder of the bill of rights, war crimes and on and on and on that the Republican president would surely continue.  Why wouldn't they?  What reason would they have not to continue to bow to their corporate masters?  The answer - no reason at all.
I switched my temporary support from Senator Clinton to Senator Obama when I perceived her campaign as using tricks and tactics invented and honed by KKKarl Rove and the rest of the League of Evil known as the Republican party.  
I say temporary support because if Hillary won the nomination I would immediately and happily switch back because there is too much at stake this time to allow the Republicans to continue to destroy America.  But I also took the time to learn about my new candidate.  I did research and read his most recent book.   Now - I know what you are thinking - a book doesn't necessarily convey the honest thoughts of the writer - and almost always portrays the writer in the best possible light.   But it wasn't what he said that impressed me so much, it was how he thought.   You got a great insight into how he resolves a problem.   
That skill is one reason why he is going to make the best President we've had in a long time (and I hold Bill Clinton up pretty high on that list).  Barack Obama can and will restore the shine America used to have.  We are now dirty and bloody and are just as bad as the Countries we deem "Evil".  We used to be that "City on a hill" - the shining example of how to do it right (don't get me wrong - we've done MANY MANY MANY things wrong - but we're still working out the kinks - we're only a couple of hundred years old. ) Most of the rest of the World used to look to us and say "That's what I want".  And I believe our finest hour was during the Presidency of Bill Clinton.  We SHINED then.  There was no doubt that America was the Greatest Country in the World - and I mean NO DOUBT.  Peace, prosperity, technological advances such as the world has never seen, giant increases in home ownership (without the scams of the current administration), you get the picture - remember - you lived it.  
I honestly believe if you can look past your anger and disappointment (again - it's not just Hillary that lost something she wanted more than anything - it's you and each of her ardent supporters) you will see that our children deserve better than the Hillary supporters voting for John McCain.   
Hillaryis44.org and it's supporters - can you imagine if John McCain gets the opportunity to nominate two Supreme Court Judges?  What would that do to our Nation.  Those two positions are so much more important to our daily lives than the person sitting in the oval office.  But your supporters are so fired up and if they follow through with their promises (threats) to vote for McCain or write in Hillary or just stay home - everything that Hillary believes in will be lost.  Am I being over dramatic?  NO.  Our way of living is threatened by a McCain Presidency.  Our rights and freedoms and economic prosperity (ya right - we're all now just barely getting by - prosperity is a dream long dead for most of us) and even our safety is under siege.  John McCain and his evil party come across with their fearmongering and threaten that if a Democrat is elected - we'll all die.  Well - I'm going to borrow a page from them and say that if John McCain is elected - we will be so much less safe than if we elect Obama.  A McCain America probably won't even be recognizable in four years.
Bush has inspired so much more hatred in the terrorists than we ever had before.  They are more organized, more determined and more lethal than they've ever been.  And that was done by the party that promised to destroy them.  Many Republicans believe John McCain is so much more of a warmonger than Bush could ever be.  He openly calls Asians "gooks" and doesn't apologize for it.  Is he looking for revenge on the Vietnamese?  Does he just want to take out his pent up anger on Iran and nuke their  asses back to the stone age?   Note to McCain - Iran is changing not because of us but in spite of us.  If we bomb them or attack them now - we will give credence to the nut job Ahmadinejad that we are nothing more than the Great Satan we've been portrayed as for years.   
The average citizen in Iran is a good person (because people are inherently good and despite what the religious crazies try to shove down our throats, we don't need Jesus for that) and like each and every one of us doesn't want to lose their lives.  They especially  don't want to die needlessly in a war. 
When it's said by Fox and the other blood sucking vampires on the right that Iranians endorse Obama for President that should be seen as a good thing.  They, like us, want peace. They don't want some senile old man with an anger management problem who likes to joke and sing about killing them with bombs winning the election - especially at the hands of disgruntled Hillary supporters.  
Friends, fellow patriots, there is too much at stake this time to bite off our noses to spite our faces.   Our brave soldiers have fought and died to protect the America that you and I believe in - not the corrupt bastardized form of Government that the Bush administration has shoved down our throats.   It's time for you and I and every single Democrat, Independent and reasonable Republican to stand together behind our leaders.  While Barack Obama may be our President and the face of our Nation to the rest of the world (as well as the best person possible to inspire greatness from the masses) - there are so many more leaders in our party who will need to be at the top of their game in order to fix the mess left to us by the Bush/ Cheney crime families.  And at the top of that list will be Senator Clinton.  
She may be the VP (and the 45th President of the United States who's instrumental in the transformation of our Country from the bottom of the barrel where we are now to the shining example for the rest of the world to follow.  She may be the leader of a Senate that is controlled by Democrats who can finally restore our freedoms, bring the animals in this administration to justice, give us universal healthcare, and protect America by going after the right terrorists.  Or she might be a Supreme Court Judge who uses her natural talents and her unwillingness to compromise on her beliefs to give us a fighting chance against Bush's appointees.  The bottom line is that America needs Hillary Clinton.  And America needs the Clinton supporters to let go of their anger and to support Barack Obama.