WASHINGTON (AP) -- A private organization established to run a third-party candidate in this year's presidential elections has thrown in the towel, saying no one mustered sufficient support for such an effort.

Kahlil (kuh-LEEL') Byrd, chief executive officer of Americans Elect, says that under the rules his group approved for an online primary, the process was ending Tuesday.

Third party presidential candidacies have rarely succeeded in U.S. politics, and Americans Elect had hoped to conduct the "Americans Elect Online Convention" this June.

But Byrd says that "as of today, no candidate has reached the national support threshold required" to enter the online convention. He adds there still is, quote, "an almost universal desire among delegates, leadership and millions of Americans who have supported AE to see a credible candidate emerge from this process."