David Letterman tried to bait him, but former President Bill Clinton was having none of it, refusing to say whether his wife, Hillary, plans to run for president in 2016.
Clinton appeared on CBS's "The Late Show" on Monday, and Letterman told him he had vacant office space in the studio if he happened to know of anyone running for president who could use it.
"I know you know. Of course you know. Why wouldn't you know?" Letterman said. "There's two people that know, maybe three. I'll bet Chelsea knows."
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Finally, Letterman asked straight out: "If she is running, to your knowledge, blink twice."
Clinton stared back with a smile on his face.
"I blinked once!" he said.
Clinton said he has no idea whether Hillary will run for the Democratic nomination, for which she is heavily favored in early polls. Hillary, Clinton said, has lots of projects she's currently working on, and she's also enjoying her free time.
"You know that if I did know I wouldn't tell you," Clinton said. "But I honestly don't know. Chelsea doesn't know, and Hillary doesn't know. And that's a good thing for America. We should focus on these big challenges now, and talk about how to get this country back on track."
He decried how presidential elections now start as soon as the last one ends. Clinton began his first campaign in October 1991, running only 13 months. In that time, he sprang from fifth place to win the Democratic nomination and the general election.
"President Obama had barely taken his hand off the Bible taking the oath of office for a second term when we allegedly started the next election," he said.