When Kirsten Gillibrand moved left on guns in 2009, she did it fast.

The moderate Democrat from upstate New York had just been appointed to the Senate and liberals were in an uproar. Then a congresswoman, Gillibrand had an A-rating from the National Rifle Association. She co-sponsored bills to roll back restrictions on firearms in the District of Columbia and to limit disclosure of gun trace information by law enforcement. Gun control advocates were stunned that she was chosen to fill the seat.

But Gillibrand’s transformation had already begun. The day of her appointment, she vowed to work on a bill to strengthen background checks with a fierce critic of her gun record, then-Rep. Carolyn McCarthy, D-N.Y. The next day, she told an audience in Harlem that she could perhaps be flexible on gun control.

The new senator proved more than flexible. She voted against the NRA’s entire agenda and received an F-rating from the group by her next election, less than two years later. Her rapid shift on guns drew a word of caution from McCarthy, who became an ally.

“I remember saying to her one time, ‘Don’t change your mind so fast – learn the issue first,’ ” McCarthy said.

Gillibrand overhauled her political identity during this period, abandoning the conservative positions that made her popular upstate and embracing or even moving further left than the liberal consensus on guns, immigration, Wall Street and same-sex marriage. As the Democratic Party itself moved left, she staked out positions popular with the party’s swelling base of liberals, a posture most evident when she called for abolishing the Immigration and Customs Enforcement agency. She has voted against President Trump’s agenda more than any other senator.

Her evolution seemed to reach its apex last week when she introduced herself as a candidate for president and a fighter for liberal values.

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