Susan Page

USA TODAY

WASHINGTON — With seven weeks until Election Day, Democratic mega-donor and environmental activist Tom Steyer is trying to convince Millennials not just to support Hillary Clinton but also to show up to vote.

Steyer, who already has contributed nearly $40 million to liberal groups during this campaign cycle, said Tuesday that he is chipping in an additional $15 million to For Our Future, a joint effort among four labor unions and a super PAC he founded called Next Gen Climate. The money won't go to TV ads but to a door-to-door campaign that aims to knock on 2 million doors in seven states.

That raises his total contribution to the group this year to $20 million. For Our Future, which says it already has knocked on 2 million doors of working families once, plans to return to make three more rounds of door-knocking to encourage an estimated 3.5 million "sporadic" voters to go to the polls.

The states are Florida, Missouri, Nevada, North Carolina, Ohio, Pennsylvania and Wisconsin — all states with Senate races in November as well.

"We think to a large extent this is a turnout election, that to a large extent it's not how you're going to vote but whether you're going to vote," Steyer told Capital Download, calling voter participation among Millennials a key to the November outcome. "This is the biggest group of people in the United States of America, and they overwhelmingly support, in theory, Secretary Clinton. If they don't turn out, that's an absolutely overwhelming fact. If they don't turn out, that's a very troubling fact."

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Voters under 35 were a crucial part of the coalition that elected Barack Obama to the White House. But they overwhelmingly supported Vermont Sen. Bernie Sanders in the Democratic primaries, and Clinton still is struggling to generate enthusiasm among what is now the nation's largest generation. Her campaign is working on it: At a speech to a youthful audience at Temple University in Philadelphia on Monday, she portrayed herself as an idealistic fighter for children and warned that Donald Trump didn't share their values.

The Democratic campaign also is deploying Sanders, Massachusetts Sen. Elizabeth Warren and Obama himself to make her case with younger voters.

In a poll last month of Millennials in 11 battleground states, Clinton won the support of just 38% on a four-way ballot, though she easily led Trump, at 20%. Another 11% supported Libertarian Gary Johnson and 6% Jill Stein of the Green Party. The online poll of 1,652 voters, sponsored by Next Gen Climate and released last week, was taken Aug. 24-30.

Sixteen percent of those surveyed said they would have supported Sanders against Trump but refused to back Clinton.

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"Let's start with the fact that when you fall in love with a candidate — and a lot of Millennials fell in love with Sen. Sanders — it's hard to give up your love, and I think that's true whether you're a Millennial or a Boomer or whatever," Steyer told USA TODAY's video newsmaker series, noting that the percentage of Sanders' hold-outs had declined from 21% in a July survey. He attributed that to an increased understanding of policy differences between Clinton and Trump.

In the August poll, 36% said there was "no real difference" between Clinton and Trump on the issues important to them.

"As they learn the facts, they are losing their deep affiliation with Sen. Sanders and realizing that Secretary Clinton is in fact a very good alternative for them," he says. "I think that Mrs. Clinton needs to talk about the issues that they care about, and I think that she is aligned with them much more than Millennials know. ... What we've seen them respond to is authenticity and issues."

Billionaire Democrat launches $25 million youth-vote push

Steyer, 59, a hedge-fund billionaire, has focused on the need for clean energy and the cause of climate change. He was the biggest individual contributor to super PACs in the 2014 campaign, contributing more than $70 million, and as of Federal Election Commission reports filed through July he was the biggest single donor during the 2016 campaign. Even so, he calls the 2010 Citizens United decision by the Supreme Court, which opened the door to such unlimited contributions, "a big, fat mistake."

"Almost the worst thing about the Citizens United decision isn't just the fact that it distorts and corrupts our politics," he says. "It's also that fact that normal Americans feel like, wow, the system is rigged against me; it's not a system that responds to me, and that is a huge threat."

He is considering whether to run for governor of California in 2018 but says he hasn't reached a decision. "The fact of the matter is, I don't know what California or the United States will look like Nov. 9," he says. "And neither does anybody else."

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