MADISON, Wis. — Democratic presidential candidate Beto O’Rourke told supporters Sunday that he’s never taken LSD and there’s “nothing” he hasn’t already revealed about his past that could come back to hurt his run for office.

The former Texas congressman – who has become known for his propensity for using the “f-word” – also promised again to clean up his language, despite breaking such past vows.

O’Rourke grabbed much attention as he wrapped up his first week of campaigning, but his challengers could be found at events from the Upper Midwest to the South. And looming over them all is the shadow of one prominent Democrat not in but not out, former Vice President Joe Biden. He has yet to announce a decision.

Speaking in front of a large map of Russia inside a coffee shop in Wisconsin’s capital, O’Rourke promised to return often, addressing concerns Democrats raised in 2016 after Hillary Clinton never campaigned in the state after her party’s primary and lost the state to Donald Trump by fewer than 23,000 votes.

“This state is fundamental to any prospect we have of electing a Democrat to the presidency in 2020,” O’Rourke said, adding that he was “really glad” Milwaukee was chosen to host the 2020 Democratic national convention. The city, which O’Rourke was visiting later Sunday, beat out Miami and Houston.

O’Rourke has already said he’d prefer to pick a woman as his running mate, should he make it that far.

O’Rourke said Sunday that it was presumptuous to commit to that so early, but that doing so would make a “tremendous amount of sense” given the number of qualified women candidates.

Meanwhile, Kirsten Gillibrand formally joined the 2020 White House race Sunday and previewed the hard line she will take against President Trump by announcing a rally outside one of his signature Manhattan properties.

The New York senator had spent more than a month traveling around the country to gauge support for a run.

Gillibrand’s announcement that she was joining the dozen-plus Democratic candidates seeking the White House came in a nearly three-minute video released early Sunday, when she says the national anthem poses this question: “Will brave win?”

She said her debut speech as a candidate will come next Sunday in front of the Trump International Hotel & Tower in New York.