A hard-fought U.S. Senate race ended Tuesday night with an impassioned concession speech from Beto O'Rourke – one that left the network airing it apologizing for O'Rourke's language.

Speaking to his supporters, O'Rourke said: "All of you, showing the country how you do this. I'm so f---ing proud of you guys."

The crowd roared its approval.

The network airing the speech, MSNBC, was less enthusiastic. Anchor Brian Williams apologized for O'Rourke's language after the network cut away.

O'Rourke's comments came as he conceded to Republican incumbent Ted Cruz after one of the most intense and best-financed campaigns in Texas history.

It's not the first time O'Rourke has used colorful language on the campaign trail. In September, Newsweek reported on a Cruz ad that suggested O'Rourke rallies were no place for children. The ad showed multiple clips of O'Rourke cursing.

The race drew national and international attention because of Cruz’s status as a former presidential candidate and because of the star power gained by the upstart O’Rourke.

O’Rourke raised close to $70 million in a campaign he started 18 month ago as a long-shot candidate. Texas has not sent a Democrat to the Senate in 30 years.

Watch the concession speech below; the strong language occurs around the 6:50 mark.

Contributing: The Associated Press; John C Moritz and Madlin Mekelburg, Corpus Christi Caller Times