El Paso, Texas (CNN) Former US Rep. Beto O'Rourke is ready to "push the button" to launch his presidential campaign, with the announcement expected to first come on social media, a source familiar with his plans told CNN.

Aware that the 2020 Democratic primary is quickly taking shape, O'Rourke is set to announce his candidacy this week, rather than launching an exploratory committee.

He will also travel to eastern Iowa beginning Thursday with a meet-and-greet event in Burlington, Democratic sources in the state said.

The three-day itinerary for his first visit to the early-voting state is intended "to allow space for him to meet voters," said another Iowa Democratic official, who spoke to O'Rourke's advisers. The trip will end Saturday with a get-out-the-vote push for a state Senate candidate in Waterloo, followed by an event in Dubuque. A Friday visit to Des Moines was considered initially, but isn't currently in the works, as O'Rourke plans to devote all three days to introducing himself to voters in eastern Iowa.

O'Rourke is in his hometown of El Paso, Texas, this week ahead of his Iowa trip. On Monday, in a short video recorded outside his house, he wore a University of Northern Iowa cap as he urged students at the school to vote in the Democratic candidate in the state Senate special election.

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