(CNN) Tom Steyer is spending another $10 million to put a second anti-Donald-Trump advertisement on national television -- this time taking aim at the President's tax overhaul push.

The ad comes less than a month after the Democratic mega-donor and billionaire environmentalist spent $10 million on a one-minute ad calling for Trump's impeachment.

The second installment of Steyer's anti-Trump ad campaign begins Thursday with a spot filmed on Steyer's ranch in Pescadero, California.

It urges viewers to sign Steyer's NeedToImpeach.com petition to remove Trump from office -- but largely focuses on a GOP tax plan that Steyer says "is really for the wealthy and big corporations while hurting the middle class." The ad's release was timed to coincide with a House vote on the GOP's tax measure.

The ad begins with Steyer recalling the 2008 financial collapse and introducing his own history -- an important element, since Steyer has left the door open to a run for president, the Senate or California governor himself.

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