At Penn State stop, Democrat Beto O’Rourke brings the 2020 fight for the White House to Pa.

In shirtsleeves and a Penn State hat, Democratic presidential candidate Beto O’Rourke brought his freshly launched campaign for the White House to Happy Valley on Tuesday, promising to seek solutions to climate change and to restore the United States to its position as a global leader, according to published reports.

If the planet “warms another degree Celsius going forward, we are screwed — that is the term the scientists use,” O’Rourke joked, according to The Morning Call of Allentown. He added that “even if we all band together in the face of this threat and this challenge, it’s not going to be enough. It’s going to take the world.”

Surrounded by a crowd of several hundred spectators bellowing Penn State’s “We are!” chant, the former one-term Texas congressman raced from topic to topic, touching on immigration, the economy, as well as health care and the opioid abuse epidemic, The Morning Call reported.

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When it came time for questions, several were pointed, questioning O’Rourke about his voting record in the U.S. House of Representatives and the lack of specificity in his speeches and his campaign website.

“When are we going to get an actual policy from you instead of platitudes and nice stories?” one woman asked.

O’Rourke responded that he’d “try to be as specific as I can,” launching into a stream of policy positions, including support for expunging marijuana arrests; passing the “Medicare for America” proposal that would expand Medicare but also seeks to maintain employer-based private insurance; increasing pay to teachers; and responding to the opioid crisis by holding pharmaceutical companies accountable and caring for those racked by addiction.

“In every single policy area, I’m trying to describe not just the goal and the aspiration but the path that we will take to get there,” O’Rourke said. “I understand if we disagree or come to different conclusions. That’s the genius of our democracy.”

O’Rourke, who unsuccessfully ran for U.S. Senate against Republican incumbent Sen. Ted Cruz last year, joins an increasingly crowded — and diverse — field of Democratic hopefuls looking to unseat President Donald Trump in 2020.

They include U.S. Sens. Kamala Harris of California, Kirsten Gillibrand of New York, Cory Booker of New Jersey, Elizabeth Warren of Massachusetts, Bernie Sanders of Vermont, and Amy Klobuchar of Minnesota.

Others in the running include former Housing & Urban Development Secretary Julian Castro; U.S. Rep. Tulsi Gabbard of Hawaii; South Bend, Ind. Mayor Peter Buttigieg; Washington Gov. Jay Inslee; and former Colorado Gov. John Hickenlooper. And floating above the field is former Vice President Joe Biden, who has strongly hinted that he’s leaning toward a run.

Even though he hasn’t even declared yet, Biden led the Democratic primary pack in a Morning Consult poll released Tuesday, The Hill reported.

Pennsylvania remains key to the Democrats’ 2020 electoral fortunes. Trump carried the state by 44,000 votes in 2016, breaking a three-decade-old streak presidential winning streak for Democrats the nation’s fifth-largest state.