The Democratic nominee for the U.S. presidency will likely be determined by the 250 superdelegates on the road to the Democratic National Convention this summer in Denver.

The race for the Democratic presidential nomination could have ended Tuesday.

But it didn’t, and it’s still anyone’s guess when the campaign between Illinois Sen. Barack Obama and New York Sen. Hillary Clinton will end.

In fact, there’s virtually no way for either Obama or Clinton to reach the magic number of delegates needed to win the nomination – 2,025 – without picking up a sizable chunk of the 250 superdelegates who have not yet given their support to either candidate. A superdelegate is a Democratic Party official who can vote at the national convention by virtue of his or her party standing or office.

“A fair number of superdelegates right now are probably less than thrilled,” KU political science professor Burdett Loomis said. “At some point, they’re going to have to make an extremely tough decision.”

In Kansas, there are nine superdelegates, one of whom is a yet-to-be-chosen member of the public. Of the other eight, three have endorsed Obama – Gov. Kathleen Sebelius, Democratic Party National Committeewoman Randy Roy and Democratic Party National Committeeman Lee Kinch – and one, Kansas Democratic Party Vice-Chairwoman Teresa Krusor, has endorsed Clinton. The other four – Rep. Nancy Boyda, Rep. Dennis Moore, Kansas Democratic Party Chairman Larry Gates and National Federation of Democratic Women Chair Helen Knetzer – remain uncommitted.

Spokespeople for Moore and Boyda said the U.S. representatives have received calls from both candidates. Gates said he expected to remain unpledged at least through the May 17 Democratic state convention. Knetzer did not answer messages left with her Wednesday afternoon.

Rebecca Black, Moore’s spokeswoman, said this election cycle has been much like every other for the congressman in terms of requests for endorsements, something he’s not done previously.

“I don’t think there’s any additional pressure to make up his mind this time,” Black said.

With the delegate count as close as it is, and only three contests scheduled between now and the end of April, it’s very possible the competition will carry into summer and possibly until the Aug. 25 convention in Denver.

Loomis, however, expects that some sort of agreement will be worked out before then, even if it is just a few days before the convention. The same thing happened in 1984 when Walter Mondale didn’t technically win the nomination until the convention; however, Loomis said, an arrangement was made beforehand.

Obstacles remain even to that, though.

“Things could unravel in the heat of decisions made at the convention,” Loomis said.

And for the first time Wednesday, one of the candidates made positive remarks about a joint Obama-Clinton or Clinton-Obama ticket. In TV interviews Wednesday, Clinton seemed receptive to the idea, though she clearly indicated she expected to occupy the top bill of such a ticket.

While lamenting that the race was still marching on, Gates, the Kansas Democratic party chairman, said he was excited and intrigued by the race as it stands.

“This is a healthy process,” Gates said. “I’m so proud that our party is in a race between people who could become the first woman and first African-American to be president.”

Loomis said he expected both candidates to be well-funded, and that any dramatic shift would come only if a major scandal or flaw were discovered in either candidate. Ultimately, he said, the candidates have views that are too similar for issues to spark a serious shift in the balance.

“On issues, Hillary and Barack are really close on a lot of things,” he said. “They’ll try to get some leverage, but I don’t think this is an issue campaign.”