The result is a shocking outcome but comes after cycles of steady gains by Democrats to put Texas in the battleground column, capping off one of the closest and most expensive races in U.S. history. The outcome could have major ramifications on Republicans’ ability to maintain control of the Senate.

“The voters have spoken, and I want to extend my congratulations to James Talarico on his election to the U.S. Senate,” outgoing Sen. John Cornyn (R-TX) said after the results were decided. “I look forward to meeting him and offering my assistance with his transition as he prepares to serve Texans in the U.S. Senate.”

Ad spending and reservations eclipsed an eye-popping $575 million for the toss-up contest, making it the most expensive non-presidential election in American history. But not far behind was the equally competitive Ohio Senate race, which also topped $500 million.

The average of recent polls showed Talarico with a steady 2.6-point edge in the closing days of the campaign, but still within the margin of error.

KEN PAXTON MAKES CLOSING PITCH TO ANXIOUS REPUBLICANS — AND EVEN SOME OPPONENTS

The election was to replace Cornyn, the fourth-term incumbent who was ousted by Paxton earlier this year in a bitter primary with the support of President Donald Trump. The race became ever more competitive for Democrats with the nomination of Paxton, whom Cornyn maintained was unfit for office due to a prior state impeachment, allegations of corruption from his own party, and a criminal indictment.

Talarico presented challenges of his own for Democrats, predominantly his progressive record as a state lawmaker, which he increasingly distanced himself from but that Republicans pointed to as evidence of a politician out of step with Texas values.