Days before he takes office, Gov.-elect Bruce Rauner has created a special $20 million war chest to push his agenda against what is likely to be strong opposition in Springfield—and lots more money is on the way.

A source close to the incoming GOP governor tells me paperwork will be filed later today disclosing that $20 million has been contributed to Citizens for Rauner, the governor-elect's campaign fund. The money won't be spent on his re-election campaign in 2018 but to help him pass legislation this spring through a General Assembly in which Democrats hold veto-proof majorities in both the House and Senate.

"There are a lot of legislators who he is going to be asking to make a lot of tough decisions," said one Rauner insider who asked not to be named. "The intent is to build a large and effective political operation in order to pursue his agenda."

Some of the money may be donated directly to legislators' campaign committees and other funds spent on their behalf. TV ads, polling and other activity on behalf of Rauner policies also is expected, the insider said. And the war chest only is "the first in a series," part of a "multipronged effort" in which other funding vehicles will be formed, the source said. “This is the tip of the iceberg.”

Rauner personally contributed $10 million to the newly reconstituted fund. Another $8 million came from Ken Griffin, the hedge-fund billionaire who was a major backer of Rauner's campaign for governor. The remaining $2 million came from GOP business exec Dick Uihlein, a frequent Republican donor.

Rauner previously contributed more than $21 million to his election campaign. That and the new money are unprecedented in Illinois politics.

In flexing his personal financial muscle after an election, Rauner appears to be following in the steps of former New York Mayor Michael Bloomberg. The latter effectively self-financed his campaigns for mayor, but also opened his wallet to allies and would-be allies after taking office, and recently has funneled tens of millions into anti-gun and other causes.

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