First in The Blast: Democrat Beto O'Rourke has pulled within 4 percentage points of U.S. Sen. Ted Cruz, R-Texas, among Texas voters, according to a new poll from an O'Rourke-allied group, End Citizens United.

The survey, conducted by the left-leaning firm Public Policy Polling, found O'Rourke, an El Paso congressman, trailing Cruz 42 percent to 46 percent. That's closer than the 8-point lead PPP gave Cruz when it surveyed the race in January for End Citizens United, a Democratic group focused on campaign finance reform.

"This is a race where we've seen an incredible amount of movement — and the momentum is entirely in Beto's favor," ECU President Tiffany Muller said in a statement. "Senator Cruz's record of serving special interest juxtaposed with Beto's refusal to take a dime of PAC money is the clearest example of how money-in-politics is defining this race. These numbers spell trouble for Cruz."

Once voters were told about O'Rourke's decision to reject PAC money, he took the lead, 46 percent to 43 percent. The January poll produced a similar result, giving O'Rourke a 2-point advantage after respondents were informed he isn't taking PAC money.

The most recent poll is the third this week to show a single-digit race between Cruz and O'Rourke. Cruz's campaign was critical of the two previous surveys, taking issue with their methodologies and samples.

PPP conducted the latest poll for ECU from Wednesday to Thursday. The firm interviewed 797 Texas voters, with 75 percent of interviews being done over the phone and the rest online. The margin of error was plus-or-minus 3.5 points.

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