WASHINGTON (AP) — President Donald Trump is responding to a California billionaire who has vowed to spend at least $10 million in advertising calling for the president’s impeachment.

Trump is using Twitter to call Tom Steyer “wacky & totally unhinged.” He says Steyer “has been fighting me and my Make America Great Again agenda from the beginning,” adding the billionaire environmentalist “never wins elections!”

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Steyer recently launched the advertising, which has been running on Fox News and other national outlets, arguing that Trump should be ousted from office. Steyer contends Trump is pushing the U.S. toward a nuclear war, is obstructing justice at the FBI and threatening to shut down news organizations he doesn’t like.

Billionaire Tom Steyer speaks during a rally and press conference at San Francisco City Hall on Oct. 24, 2017, in San Francisco. (Getty Images)

Steyer wants viewers to call their members of Congress and tell them to bring articles of impeachment.

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Democrats such as House Minority Leader Nancy Pelosi of California think impeachment attempts are not worthwhile because they will fail in the Republican-led Congress and could energize GOP voters heading into the next election.

Steyer plans to spend eight figures to air the television ads nationally, but he would not give an exact amount. His investment comes as he considers running against U.S. Sen. Dianne Feinstein, a fellow Democrat.

Steyer has poured his wealth into a variety of political efforts, mostly focused on stopping climate change.

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