The former vice president was never the group's favored candidate to take on Trump, with a February survey of its members showing that just 6 percent picked Biden among the then-crowded Democratic presidential primary field, well behind Elizabeth Warren and Bernie Sanders.
But the group's grassroots members and local chapter leaders voted overwhelmingly to support Biden, the apparent Democratic nominee, with Indivisible co-founder Ezra Levin calling him "Abraham Lincoln compared to Donald Trump."
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About 95 percent of Indivisible's members backed endorsing Biden.
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