Last Updated May 30, 2016 8:48 PM EDT
Weekly Standard editor Bill Kristol sent out a provocative tweet Sunday, calling for a "heads up over this holiday weekend" that another presidential candidate -- an independent -- would be entering the race for the White House.
Kristol said no more Sunday evening, beyond the tweet, which referred to the yet-to-be-named candidate as "an impressive one, with a strong team and a real chance."
Donald Trump unleashed a series of tweets in response, insulting Kristol, and both badgering the GOP and calling on the party to unite against this unnamed new opponent. He also implied in his tweets that an independent run would mean a Clinton victory and a liberal nomination to the nation's highest court.
Kristol says he was traveling, so his response to Trump's tweets came Monday:
Kristol's original tweet may have been a little wishful, though. A source who is also part of the effort to recruit a candidate to run against Donald Trump and Hillary Clinton told CBS News' Julianna Goldman not to expect an announcement for a couple of weeks.
The Washington Post had reported a little over two weeks ago that GOP operatives had mounted an effort to derail Donald Trump by bringing in another conservative candidate. Goldman confirmed that several names were being considered at the time, including former Oklahoma Sen. Tom Coburn, former Secretary of State Condoleezza Rice and retired Army Gen. Stanley A. McChrystal.
Independents sense an opening -- Trump and Hillary Clinton have the highest unfavorable ratings in CBS News/New York Times polls going back to 1984, when the question was first asked.
But the time for an independent candidacy is running short -- the deadline to make it onto the Texas ballot for the general election has already passed, and North Carolina's deadline is coming quickly on June 9.