EL PASO, Texas/WASHINGTON (Reuters) - Beto O’Rourke, the Texan who gained a national following with his long-shot election battle against U.S. Senator Ted Cruz last year, will seek the 2020 Democratic presidential nomination, a source close to the campaign said on Wednesday.

O’Rourke, a 46-year-old former three-term U.S. representative from West Texas, will make his announcement via video on social media at 7:30 a.m. EDT (1130 GMT) on Thursday, the source said.

“I’m really proud of what El Paso did and what El Paso represents,” O’Rourke said of his hometown in a text to TV station KTSM, which first reported his entry into the race. “It’s a big part of why I’m running. This city is the best example of this country at its best.”

O’Rourke planned to follow his announcement with a trip to Iowa, the state that will hold the first Democratic nominating contest in February 2020.

With his presidential effort, O’Rourke is hoping to leverage the fame he gained with his Senate race. He was a heavy underdog when he challenged Cruz, a Republican, in mostly conservative Texas, but he quickly demonstrated an ability to draw capacity crowds and raise money from voters nationwide.

His Senate bid generated a torrent of media attention and excited voters in a party desperate for fresh political faces. He lost the race by less than 3 percentage points, the tightest U.S. Senate contest in the state in four decades.

Early opinion polls on the 2020 race have consistently ranked O’Rourke in the top tier of more than a dozen declared or possible Democratic contenders, behind former Vice President Joe Biden, who has not yet said whether he is running, and U.S. Senator Bernie Sanders, a 2016 presidential contender who announced his 2020 candidacy last month.

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Vanity Fair quoted O’Rourke as saying in an interview published on Wednesday that he was aware of his disadvantage as a white man at a time when many in the Democratic Party want a woman or a person of color for president.

“So if I were to run, I think it’s just so important that those who would comprise my team looked like this country. If I were to run, if I were to win, that my administration looks like this country. It’s the only way I know to meet that challenge,” O’Rourke told the magazine.

KEEPING IN PUBLIC EYE

Since his Senate bid ended, O’Rourke has worked to keep himself in the public eye, regularly staying in touch with his supporters and sitting for an interview with Oprah Winfrey.

He took a well-publicized road trip across the American Southwest, stopping at colleges and diners. He visited with students in the key swing state of Wisconsin.

He also held a rally in El Paso on the same night in February that Republican President Donald Trump staged one there. Both events in the Texas city that borders Mexico drew thousands and put the two men’s divergent positions on the border wall on sharp display.

In El Paso, Trump ridiculed O’Rourke as “a young man who’s got very little going for himself, except he’s got a great first name.” O’Rourke accused Trump of stoking “false fear” about immigrants.

Starting with the Iowa caucuses next year, the Democrat who amasses the majority of delegates nationwide in a series of nominating contests will be nominated at the party’s convention in the summer, and will likely face Trump in November’s general election.