Both Biden and Sanders want to boost Social Security benefits. So why are they fighting on the issue?

Top Democratic presidential candidates all want to boost Social Security benefits.

But two of the candidates — Sen. Bernie Sanders (I-Vt.) and former vice president Joe Biden — have come to figurative blows over this very issue.

The crux of the argument: whether Biden has fought to protect or previously backed cuts to the program.

On Wednesday, Biden denied he would cut Social Security benefits if he wins the White House, in an interview on MSNBC’s “Morning Joe.”

But Sanders’ campaign has questioned Biden’s record because he has called for cuts to the program in the past. In response, Biden and his campaign have accused Sanders’ team of misrepresenting recent comments and even doctoring a recent video.

Both Biden and Sanders have outlined measures to expand, not cut, benefits as part of their 2020 presidential campaign platforms.

Both candidates also call for raising Social Security payroll taxes from their current $137,700 cap in order to get more money into the program.

That would pave the way for benefit increases, which both candidates back. Their plans, however, differ.

Biden calls for increasing benefits for those who have been receiving retirement checks for at least 20 years, as well as for widows and widowers. His plan also would set a new minimum benefit, so that workers who have paid into the system for at least 30 years would get a benefit equal to at least 125% of the federal poverty level.

Meanwhile, Sanders calls for giving $1,300 more per year to seniors with incomes of $16,000 or less. His plan also calls for raising benefits for low-income workers as well as higher annual cost-of-living adjustments.

Despite those seemingly compatible goals, the two candidates are at odds.

Sanders’ team has been promoting old footage of Biden, a former senator representing Delaware, discussing the future of Social Security on the Senate floor.

“When I argued that we should freeze federal spending, I meant Social Security, as well,” Biden says in the Jan. 31, 1995 clip discussing the balanced budget amendment.

While Democrats had a history of backing Social Security expansion, that changed in the 1990s, according to Nancy Altman, president of Social Security Works, an advocacy group.

At that time, a campaign emerged to convince the general public that the program was in crisis and would go bankrupt, she said.

Records show that Biden called for cutting benefits even before then.

“Biden had a long history of being part of that and being open to a deal with some increases and some cuts,” Altman said.

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Now, the concern among some is that when it comes down to negotiations with Republicans, Biden would be willing to make concessions to get something done.

And that could mean reducing benefits by raising the retirement age or using so-called means testing, which would reduce benefits for higher-income individuals, Altman said.

Still, Jared Bernstein, who worked as an economic advisor to Biden in the Obama administration, said that Biden has honest intentions when it comes to protecting Social Security.

“He was/is as staunch a supporter as you’ll find, both for economic and political reasons,” Bernstein said.

Biden’s designs for the program have also been met with support from Social Security advocacy organizations.

“Everything in the Biden plan on strengthening Social Security we endorse, including putting the program on solvent ground,” said Max Richtman, president and CEO of the National Committee to Preserve Social Security & Medicare.

Sanders has a much stronger record on Social Security, Richtman said. However, the fight between the two is not helping the larger cause, he said.

“The candidates would be well served to focus less on the differences that they might have than what the Trump White House has been doing with Social Security,” Richtman said.

Red flags for Social Security advocates have included cuts to Social Security funding in the president’s budget, or new efforts to overhaul claiming rules for the disability program.

Trump was the only Republican candidate to come out against Social Security cuts in the 2016 election.

But in an interview with CNBC on Wednesday, Trump said entitlements would be something he would consider “at some point.”

That prompted concern from Social Security advocates that he plans to cut benefits. The White House denied this in a statement.

“With no benefit cuts, President Trump is keeping his commitment to the most vulnerable Americans especially those who depend on Medicare and Social Security,” White House spokesman Judd Deere said.