Sri Preston Kulkarni, 39, received 9,466 votes (nearly 32 per cent), while his fellow Democrat Letitia Plummer got 7,230 votes (24.3 per cent) in the Democratic primary in Texas' 22nd congressional district.
Yet there is also serious cause for concern, as some Democrats seem intent on sapping that energy in an attempt to reassert control of the party. They support this president. In midterm election with a controversial president's performance as material for a referendum, this doesn't exactly look like sunny news for Republicans.
The Pennsylvania district has more registered Democrats than Republicans, but for years its residents have elected GOP candidates.
Controversy has arisen around the names of the candidates as Cruz, a staunch conservative and Catholic, unveiled a political advertisement featuring a song accusing O'Rourke - who uses a common Latino first name, although he is not of Latino descent - of changing his name to win voters.
"The extreme left right is energized and angry", said Cruz.
"Left-wing rage may raise a bunch of money from people online, but I don't believe it reflects the views of a majority of Texans", he told reporters after winning the nomination.
"We can get into name calling and talk about why the other person is such an terrible guy, or we can focus on the big things we want to do for the future of our country", O'Rourke responded.
"Eighty-seven percent increase in turnout is just something that you never would expect to see", he said, pointing out that while Republican turnout increased 15 percent, "they're coming out at rates that match what you would expect for off-year elections". "It's a uniquely anti-Trump state, because it has a rare combination of diversity and a suburban professional class". Those results had a higher margin of error but showed Democratic enthusiasm in congressional districts held by Republicans. That's more than two and a half times the 41 candidates in the last midterm elections in 2014. Republicans also had more candidates than in 2014 - 102 vs. 72 - but failed to run anyone in four Democratic-leaning districts. The victor faces Republican incumbent Pete Sessions in November.
In years past, the races would have mattered little to a national Democratic Party that consistently fails to compete in the state. Tuesday's primary in deep-red Texas did not definitively prove they can't do it.
Jeanne Atkins, chairwoman of the Oregon Democratic Party, said she was optimistic about the race, and that the performance of the Trump administration would cast Democratic candidates in favorable light statewide.
"Donald Trump got crushed here in 2016, got sent a thunderous message with our sweeping victories in 2017, and his approval rating is about where the Titanic was when it was found", Swecker said in a statement.
The Democrats had an 80 percent turnout in early voting. "I think voters are starting to be in on the joke so to speak", he said, adding voters were taking a "wait-and-see" approach to "what he actually does instead of just reacting to his tweets and off-the-cuff remarks at press conferences". "And I share some of those frustrations".
GOP operatives have gleefully watched the drama unfold. The Democratic Congressional Campaign Committee published opposition research on congressional candidate Laura Moser, highlighting that she wrote she wouldn't want to live in Paris, Texas, again. Former Dallas County Sheriff Lupe Valdez and Houston businessman Andrew White face a runoff in May. She is running against Lizzie Pannill Fletcher, a lawyer endorsed by the pro-choice, Democratic women's organization, Emily's List.
"It's rivaling a presidential year, which is unprecedented", he said.