What is Lone Star Rising?

The PAC disclosed it received $3.75 million from another Super PAC called Government That Works PAC, which itself received $4 million from the Sixteen Thirty Fund, a leading dark-money hub for Texas Democrats previously associated with Swiss billionaire Hansjörg Wyss and Democratic megadonor George Soros. Among the notable individual donors were LinkedIn cofounder Reid Hoffman, who gave $500,000, and Austin philanthropist Simone Coxe, who contributed $400,000.

That is the tension at the heart of Talarico's campaign. He has built his entire message around getting billionaire money out of politics, yet he has responded to questions about Lone Star Rising by saying he is not going to "unilaterally disarm." His campaign spokesman added that "when James Talarico has the power to change federal law in the U.S. Senate, he will fight to ban super PACs like this one."

Lone Star Rising spent nearly all of the money it raised on his behalf throughout the first quarter of the election year. It has remained the dominant outside force supporting him through the general election, though the sums on the Republican side dwarf it. Texas PAC, associated with the Senate Leadership Fund and Senate Majority Leader John Thune, booked $117 million in ads in Texas to help Paxton, with reports suggesting the PAC could spend as much as $200 million before election day.

A second pro-Talarico PAC, Moment of Truth PAC, launched by a bipartisan group of campaign operatives, aims to deploy advertising that "gives Republicans permission to defect" to Talarico and makes him "safe for moderates." But Lone Star Rising remains his primary outside backer.

Where the race stands: Talarico leads Paxton in nearly every poll, ranging from one to six percentage points, with the RealClearPolitics average showing him ahead 47.6% to 44.6%.