In a crowded scramble, Beto O'Rourke broke through in a way most candidates could only dream of with his 2020 entry this morning.The big picture: For a candidate polling in the single digits, O'Rourke has a huge national profile, as shown by the instant response to this morning's announcement.Drudge banner: "BETOMANIA"Trump mocked his announcement video: "“He has a lot of hand movement -- I’ve never seen anything like it ... Is he crazy or is that just the way he acts?”Pelosi: “Beto has brought a good deal of vitality to Congress ... when he came, he came as a real champion for the environment.”Early House Democratic endorsements: Stephanie Murphy (D-FL), Kathleen Rice (D-NY), Veronica Escobar (D-TX) and Sean Patrick Maloney (D-NY).Between the lines: "If there’s an elevator pitch for O’Rourke’s presidential candidacy, that’s more or less it: 'I came this close to turning Texas blue. Imagine what I could do nationally,'" FiveThirtyEight notes."O’Rourke won big in cities like Dallas, Houston, Austin and San Antonio. Not just that, but Texas saw an astounding 3.7 million more votes in 2018 than it did in the midterm elections four years earlier.""O’Rourke outperformed Hillary Clinton by about 6 percentage points in the state."What's next: O'Rourke's formal campaign kicks off in El Paso on March 30.In the meantime, pay attention to whether his campaign releases early fundraising or volunteer numbers. The current leader on those metrics is Bernie Sanders, who hauled in $5.9 million in his first 24 hours.Go deeper: Beto O'Rourke: Everything you need to know about the 2020 candidate