The text message appeared to be from someone in the Beto O’Rourke campaign. It asked its recipient to help “transport undocumented immigrants to the polls.”

An O’Rourke campaign spokesman says the sender was an imposter.

“That was not an approved message by the campaign,” spokesman Chris Evans said. “It was sent by an imposter. But we’re continuing to look into what happened.”

The screenshot of the text message was posted on Twitter by @JerryOchoa Wednesday afternoon. The message read, “Hi, it’s Patsy here with Beto for Texas. We are in search of volunteers to help transport undocumented immigrants to polling booths so that they will be able to vote. Would you be able to support this grassroots effort?”

Above the tweet Ochoa wrote, “This is an actual text a friend in Texas just received. It is NOT from the Beto campaign. Very slick, Ted Cruz & Texas Republicans.”

Emily Miller, a spokeswoman for Sen. Ted Cruz’s campaign, said: “Our campaign had no involvement in the alleged abuse of the O’Rourke campaign’s texting platform. We don’t condone anyone who would engage in such action.”

The O’Rourke campaign has sent out numerous text messages in support of his run for U.S. Senate against Cruz, the incumbent and favorite, and has managed to close the gap between them in recent polls.

President Trump said last week that he plans to come to Texas in October to help Cruz’s campaign.