Does Hillary Clinton really believe she can overtake Barack Obama among elected delegates? No way. The math is dead against her and she’s a realist. Even after Pennsylvania, Obama still leads by more than 140 in elected delegates. They’ll likely break even in Indiana and he’ll win North Carolina where one third of the vote is African-American. After that? If she wins Kentucky, West Virginia, and Puerto Rico by 15 points and they break about even in Guam, North Dakota, Montana, and Oregon, she’ll still trail him by at least 130 votes among elected delegates.

Does she believe she can persuade super delegates to vote for her? Again, probably not. Obama has steadily eroded her edge among super delegates and now they are almost tied among committed super delegates. And the prevailing sentiment among those that remain is not to overturn the will of the voters.

So why is Hillary still running so hard? Why is she especially focused on pushing up Obama’s negatives?

Until the last vote is counted on June 3rd, we can chalk up her persistence to determination, courage and sheer obstinacy. But if she persists in her candidacy after the last primary, we must begin to consider whether she has an ulterior motive.

Does Hillary want to beat up Obama so that he can’t win the general election in November, assuring McCain of the presidency so that she can have a clear field to run again in 2012? Obviously, if Obama beats McCain, Hillary is out of the picture until 2016, by which time, at 69 years old, she might be too old to run. But if McCain wins, she would have to be considered the presumptive front runner for the nomination, a status which she might parlay into a nomination more successfully than she has been able to do this year.

Every day that she stays in the race and punches Barack Obama, she must realize that she is decreasing his chances of getting elected in November. Each time that she waves the bloody shirt and says that only she is strong enough to fight the war on terror, she obviously raises doubts about Obama’s strength and leadership. Every time she criticizes him for not switching pastors or for saying downscale white voters are bitter, she raises issues that are very destructive to Obama should he win the nomination.

When does fighting for the nomination in 2008 end and seeking to sabotoge Obama’s chances in November to keep her options alive for 2012 begin? Doubts about Hillary’s motivation are going to keep on growing with each inconclusive primary. After she loses North Carolina and fails to carry Indiana by any significant margin (North Carolina has twice as many delegates as Indiana), people will begin to wonder out loud about why she is staying in the race. And if she remains obdurate after the last votes are cast on June 3rd, it will become an increasingly accepted presumption that she is running a campaign of sabotage against Obama.

There is a way to run without waging a scorched earth campaign. Mike Huckabee continued to fight for the Republican nomination until McCain reached the magic number to clench the battle and did not attack McCain. He waged a positive campaign and exercised his right to stay in the contest as long as it was undecided without hurting the party’s chances in November. Obviously, Huckabee could have attacked McCain and drawn more votes for his candidacy, but, in the interests of party victory, he chose not to do so.

Why isn’t Hillary making the same choice?

In 2004, it is pretty obvious that Hillary did nothing to help John Kerry beyond giving a speech at the convention and waging a token campaign on his behalf. Bill did even less. Their goal was obvious: they wanted Kerry to lose to Bush so that Hillary could run in 2008. Is she playing the same game now? Only time will tell.