Rep. Silvestre Reyes (D-Texas) was ousted in Tuesday’s primary to former El Paso City Council member Robert “Beto” O’Rourke.

The former chairman of the House Intelligence Committee was the sixth House incumbent defeated this cycle — and the third to fall to a non-incumbent.

O’Rourke won by about 3,000 votes, taking 50.5 percent — just enough to avoid a runoff with Reyes.

“Can you all just confirm for me that this is really happening?” O’Rourke asked a crowd of supporters late Tuesday night. “I feel great. We just ran a really great campaign,” he added.

Of Irish descent but a fluent Spanish speaker, O’Rourke is expected to easily win the general election in this heavily Democratic, 78 percent Hispanic district.

President Obama endorsed Reyes, and former president Bill Clinton campaigned for him. But the eight-term congressman was targeted by an anti-incumbent super PAC, the Campaign for Primary Accountability, which spent $240,000 on the race.

The El Paso Times endorsed O’Rourke, saying Reyes “has stood on the sidelines” when it comes to district-level issues, while the challenger was focused on his constituents.

Reyes made an issue out of O’Rourke’s support for marijuana legalization, which the congressman opposes. In one Reyes ad, a group of children say “no” to drugs while “Beto O’Rourke wants to legalize drugs” flashed across the screen. O’Rourke also criticized Reyes for directing campaign funds to family members.

The 67-year-old congressman told the El Paso Times that his opponent “deliberately ran a nasty, dirty campaign” and blamed the super PAC helping him.

The Campaign for Primary Accountability, which has had a hand in defeating four of the six House incumbents so far, spent about $240,000 on the race.

Many other key Texas congressional primaries are going to runoffs.

* In the competitive 23rd district, former congressman Ciro Rodriguez and state Rep. Pete Gallego are headed for a runoff after neither secured 50 percent of the vote. Gallego is a favorite of the national Democratic Party to face freshman Rep. Quico Canseco, who defeated Rodriguez in 2010.

* Reps. Lloyd Doggett (D-Texas) and Ralph Hall (R-Texas) easily turned aside primary challenges. The Campaign for Primary Accountability spent money against Hall as well.

* All four of the state’s new congressional seats — the 25th, 33rd, 34th and 36th — will feature runoffs on the side that is most likely to win in November. Crowded primaries in each case meant no candidate cleared even 40 percent of the vote. Republicans are likely to win the 25th and 36th, while Democrats are favored in the 33rd and 34th.

* There will also be a GOP runoff in retiring Rep. Ron Paul’s (R-Texas) district. Former congressman Nick Lampson, meanwhile, easily won the Democratic primary.