Former Secretary of State Hillary Clinton speaks to a packed rally to launch Asian Americans and Pacific Islanders for Hillary in San Gabriel, California on Thursday January 7, 2016. (Photo by Melina Mara/The Washington Post)

Seeing gun control as a rare opportunity to outflank Sen. Bernie Sanders from the left, Hillary Clinton sought Friday to paint the Vermont senator as out of step with liberal Democrats and now also with the White House.

In an unusual MSNBC interview by Clinton and online messages and a telephone news conference by her campaign, the Clinton organization said Sanders's camp is misrepresenting his record.

"I think Senator Sanders has been wrong on gun safety," Clinton said in a telephone interview with Chris Matthews, host of the cable network's "Hardball" program. She called gun control a central issue of the 2016 campaign.

"It represents a very clear choice in a Democratic primary."

She and her campaign aides pointed to an op-ed from President Obama on Friday that warned his support for a 2016 candidate is contingent on support for more gun control.

Sanders has a mixed record on gun control, including a 2005 vote in support of legal protections for gun manufacturers. Clinton regularly denounces the protection, saying that no other industry gets the same treatment.

"The Democrats have a real choice here," Clinton said in the rare telephone call-in interview. "I think it's important for Democrats to know that 10 years ago, gun safety advocates wanted to make gun makers and sellers have to go to court to answer for their reckless disregard of human life, because, after all, if an auto company sells an unsafe car, you can sue them.  Unsafe food, unsafe tools, unsafe toys.  The makers can all be sued."

"When it really mattered, Senator Sanders voted with the gun lobby and I voted against the gun lobby," Clinton continued. "This is a significant difference and it's important that, you know, maybe it's time for Senator Sanders to stand up and say I got this one wrong."

During a campaign appearance later Friday night in Cedar Rapids, Iowa, Sanders did not address his votes on the liability legislation but he lamented the amount of gun violence in the country and praised Obama's efforts to address it.

“We have got to do the best we can to try to end mass killings in America, and I agree with the president," Sanders said, ticking off a number of "common-sense" measures he supports, including strengthening background checks and closing loopholes that allow some some gun buyers to circumvent them.

The gun issue, while not new, has gained new resonance as the Iowa caucus vote nears and Democrats express stronger preferences for gun control than in recent past elections. For Clinton, gun control offers a way to use her own Senate voting record, now eight years in the past, to address a current issue about which she feels strongly. It gives her a means to outflank Sanders from the left, where the base of his support lies. And it gives her a way to bind herself to Obama, who remains broadly popular among Democrats and whose recent activism on guns appears to be endearing him to liberals.

"Standing up to the gun lobby is a real difference between Clinton and Sanders," the campaign wrote in an online essay distributed to supporters. "President Obama noted that gun safety is a voting issue for him and should be for everyone."

"I will not campaign for, vote for or support any candidate, even in my own party, who does not support common-sense gun reform," Obama wrote in the New York Times op-ed piece. That was a clear reference to Sanders, and a grace note to Clinton.

Obama joined a telephone call for supporters Friday to discuss "how we can help stop our gun violence epidemic," an email to Democrats said. Democratic National Committee chairman Rep. Debbie Wasserman Schultz of Florida sent supporters a separate message saying "I'm proud to stand with the president."

The Sanders campaign responded Friday, with a top official claiming that there was "no daylight" between Sanders and the White House.

"That's just not true," Clinton campaign chairman John Podesta told reporters Friday.

White House press secretary Josh Earnest said Friday that should Sanders become the Democratic nominee, Obama would "examine his record."

The Sanders campaign later responded on multiple fronts. A campaign spokesman said the Clinton camp had gone into "attack mode" because of a new poll out of New Hampshire showing Sanders with a growing lead. The poll, released by Fox News, put Sanders ahead of Clinton, 50 percent to 37 percent.

"Secretary Clinton and her team are getting nervous and nasty because the so-called inevitable nominee anointed by the establishment eight months ago doesn’t look so inevitable anymore," said Michael Briggs, communications director for the Sanders campaign.

The Sanders campaign also issued a statement supporting Obama's executive actions on gun control, including narrowing the so-called gun show loophole by which some gun sellers can avoid federal background checks. All those actions are opposed by all the leading Republican candidates.

“Throughout his career in Congress, Sanders has voted for strong gun safety measures, including a ban on assault weapons, improved background checks and eliminating the gun-show loophole," Sanders campaign manager Jeff Weaver said. Sanders, he added, "thinks Congress should re-examine" the manufacturers’ liability.

Clinton, Weaver said, "has a record of flip flops."

"Today she’s attacking Bernie on guns. Eight years ago she attacked Barack Obama on guns,” he added.

On Twitter, Sanders posted literature from Clinton's 2008 campaign in which she suggested Obama had taken varied stances on gun control depending on the audience he was addressing.

As a Senate candidate in 2000, Clinton favored a national handgun registry. But when running for president in 2008 she said federal “blanket rules” on guns did not make sense.

“Maybe Secretary Clinton should apologize for attacking the president in 2008 because he was too strong on gun control,” Weaver said. “As is the case with so many issues on which she has flip flopped, voters have to ask themselves which Hillary Clinton is asking for their vote,” Weaver added.

Clinton and Sanders will participate in a candidate forum Monday in Iowa, and will debate next weekend in South Carolina. Sanders trails Clinton in Iowa and leads her in New Hampshire in most polls.