Texas Democrats have prodded him on this score as well, but few expect Mr. O’Rourke to confine his ambitions to another state-level race. After prolific success with small-dollar donors during the midterms, Mr. O’Rourke is likely to have little trouble raising enough money to get a presidential run off the ground. His presence could energize some crucial voting blocs, like young people, who formed much of his coalition in Texas.
“If he got in, it would be a pretty big game-changer,” said Eliana Locke, who leads the College Democrats at the University of Wisconsin-Madison, where Mr. O’Rourke met with students last month.
Supporters also say it is laughable that some liberals, particularly allies of Mr. Sanders, have described Mr. O’Rourke as a squishy moderate because of a congressional record that sometimes veered toward centrism.
More recently, Mr. O’Rourke moved well to the left of many 2018 Democrats by raising the prospect of impeaching Mr. Trump; argued for the destruction of existing border barriers between El Paso and Mexico; and, in perhaps his most widely seen social media moment, defended the professional football players who were kneeling in protest during the national anthem.
“In Texas, Ted Cruz called me a socialist. I’m too liberal for Texas,” Mr. O’Rourke told the students in Wisconsin. “Outside of Texas, people say, ‘Is he really a Democrat? I think he’s a closet Republican.’ I don’t know where I am on a spectrum, and I almost could care less. I just want to get to better things for this country.”
Mr. Ortega, the friend from the City Council, suggested that part of Mr. O’Rourke’s appeal owes to his self-awareness on matters of substance: He knows what he doesn’t know and is unafraid to concede that a question extends beyond his expertise.
“He’s not the kind of guy who’s going to give you a made-up, half-baked answer,” Mr. Ortega said.
For now, supporters would settle for the fully baked answer he is keeping to himself: Is he in or out?