WASHINGTON -- Hillary Clinton used to avoid uttering the name of her main rival for the Democratic presidential nomination, Sen. Bernie Sanders (I-Vt). But that phase of the race has definitively ended, with Clinton and her team staging a multi-pronged attack on Sanders in the first weeks of the new year.

Clinton herself has laid into Sanders in the last two weeks, unspooling a new tactic of directly attacking her competitor. Her campaign staff began criticizing Sanders in earnest last autumn, but until recently, the candidate herself had mostly focused on introducing her own policies and criticizing those of the Republican contenders.

The most recent anti-Sanders salvo came last week. The Clinton campaign had highlighted Sanders’ votes to give gun suppliers legal immunity previously, but took the opportunity to re-focus scrutiny on the senator’s gun record after President Barack Obama wrote in a New York Times op-ed Thursday evening that he would not endorse any candidate who disagreed with him on gun reform, like repealing the immunity law. When Sanders’ campaign said that there was “zero daylight” between the senator and Obama on gun control on Friday, Clinton’s campaign pounced.

“The Sanders campaign has understandably tried to eliminate any distinctions between their candidate’s record and President Obama’s,” Clinton spokesman Brian Fallon said in a press call. “Of course this just isn’t true.”

Sanders defended his votes for the immunity law last year. In June, his campaign manager said the senator would likely vote for it again, were it to come up.

“This was a hugely consequential piece of legislation and Sen. Sanders has spent the duration of this campaign actually defending the liability vote,” Clinton campaign chair John Podesta said on the call. “It’s time for Sen. Sanders to join President Obama and Hillary and be willing to take this issue on, to stand up to the gun lobby and be clear on his position.”

Sanders campaign manager Jeff Weaver said in a call Friday afternoon that “the Clinton people have obviously not read the news clips,” because Sanders said in October that he was open to re-examining the liability bill. Weaver said Sanders “strongly supports the president’s initiatives” on gun control, calling the liability vote “a false issue.”

“This is old news,” Weaver said. “The conversation, I think, that they don’t want to have is the conversation about why Secretary Clinton doesn’t support the family medical leave bill that Democrats are supporting in the House and Senate, why she opposes that, her record on Wall Street and a host of other issues.”

Clinton herself pressed the liability vote issue further on Friday, calling into MSNBC’s “Hardball” with Chris Matthews to suggest that “maybe it's time for Sen. Sanders to stand up and say, ‘I got this one wrong.’”

Sanders on Sunday wouldn’t say his vote was a mistake, but did say he would vote “to revise” the bill.

Clinton said later Sunday that Sanders’ “excuses ... to avoid responsibility for this vote which the NRA hailed as the most important in 20 years, points at a clear difference … that Democratic voters in our primary can take into account.”

The Clinton campaign's aggressive 2016 tactics began the day before Sanders was to give a major speech on financial policy. The campaign’s chief financial officer issued a pre-emptive statement Jan. 4 arguing that Sanders was being soft on Wall Street by taking “a hands-off approach” to regulating the so-called shadow banking sector. Sanders fired back in his speech, pointing out that Clinton has benefited from Wall Street campaign contributions and “very generous speaking fees.”

Clinton’s campaign also has gone after Sanders on paid family and medical leave. In November, Sanders questioned why Clinton had not yet endorsed legislation supported by congressional Democrats that would guarantee three months of paid leave for employees who have children, and for workers diagnosed with serious medical conditions, funded by a small payroll tax. One day before Sanders held a press conference in Iowa to again tout his paid family leave approach and to criticize Clinton on the issue, Clinton’s campaign said she would have the wealthy, rather than workers, “pay their fair share in taxes” to fund the program.

“Hillary believes we can do this without asking working people to pay for it,” senior policy adviser Ann O’Leary said Thursday. Clinton has promised that she wouldn’t increase taxes on families making less than $250,000 annually.

In his speech on Friday, Sanders said he “strongly disagreed” with Clinton’s paid leave proposal.

“Apparently Secretary Clinton believes that a $1.61 payroll tax for the average worker is too high a price for three months of paid family and medical leave,” he said. “If President Franklin Roosevelt had taken the same position that a small payroll tax is unacceptable, we would not have Social Security. If President Johnson had taken the same position as Secretary Clinton that a small payroll tax was unacceptable, then we would not have Medicare.”

With the next Democratic primary debate set for Sunday, the candidates will have one last high-profile opportunity to make their case that the other isn’t sufficiently progressive or electable before the Iowa caucuses on Feb. 1, where Clinton holds a narrowing lead.

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