Former Vice President Joe Biden pointed to conservative victories in Thursday's United Kingdom elections as an example of why the Democratic Party should not move too far to the left, according to Politico.

During a campaign fundraiser in San Francisco, Biden, who has presented himself as a relatively moderate candidate in the 2020 Democratic presidential primary, said that the Conservative Party in the U.K. won so convincingly because the liberal Labour Party went too far left.

"Boris Johnson is winning in a walk," Biden said of the British prime minister. "Look what happens when the Labour Party moves so, so far to the left. It comes up with ideas that are not able to be contained within a rational basis quickly."

Biden is indeed moderate on some major issues compared to the candidates polling in second and third place, Sens. Elizabeth Warren (D-Mass.) and Bernie Sanders (I-Vt.). Sanders is an open socialist, and Warren, although she claims to be a capitalist, favors the same far-left, big-government policies as Sanders.

While Sanders and Warren favor a federal government takeover of health care through Medicare for All, Biden believes that program is too expensive and not what most Americans are looking for. Biden is running on a health care plan that expands on Obamacare.

Biden regularly expresses optimism about his ability to work with Republicans to get things done if elected president, while Warren and Sanders take a more adversarial tone toward their political rivals, showing much less desire to seek compromise. But Biden points out that he has a significantly stronger resume of legislative accomplishments than either of them.

The success of Boris Johnson, the prime minister who has been compared to President Donald Trump, will boost the belief that Trump can be re-elected, Biden said.

"You're also going to see people saying, 'My God, Boris Johnson, who is kind of a physical and emotional clone of the president, is able to win,'" Biden said.