Sen. Bernie Sanders, I-Vt., speaks as he kicks off his 2020 presidential campaign at Navy Pier in Chicago, Sunday, March 3, 2019. Over the next several weeks, Sanders will travel to Iowa, New Hampshire, South Carolina, Nevada, and California. He will then return to Burlington, Vt., for the official launch of his campaign. (AP Photo/Nam Y. Huh)
Nam Y. Huh/AP
Sen. Bernie Sanders, I-Vt., speaks as he kicks off his 2020 presidential campaign at Navy Pier in Chicago, Sunday, March 3, 2019. Over the next several weeks, Sanders will travel to Iowa, New Hampshire, South Carolina, Nevada, and California. He will then return to Burlington, Vt., for the official launch of his campaign. (AP Photo/Nam Y. Huh)
Now playing
01:46
Bernie Sanders releases his tax returns
CNN
Now playing
02:58
Avlon: This shows that crazy has a constituency
CNN
Now playing
07:27
CNN anchor pushes back on Texas state lawmaker's defense of voting bill
CNN
Now playing
01:12
Tapper asks Buttigieg for infrastructure plan timeline
Now playing
02:48
GOP governor calls Trump's RNC remarks 'divisive'
WASHINGTON, D.C. - APRIL 19, 2018:  The U.S. Supreme Court Building in Washington, D.C., is the seat of the Supreme Court of the United States and the Judicial Branch of government. (Photo by Robert Alexander/Getty Images)
Robert Alexander/Getty Images
WASHINGTON, D.C. - APRIL 19, 2018: The U.S. Supreme Court Building in Washington, D.C., is the seat of the Supreme Court of the United States and the Judicial Branch of government. (Photo by Robert Alexander/Getty Images)
Now playing
02:39
SCOTUS blocks California Covid restriction on religious activities
rep jim clyburn georgia voting law jim crow sot sotu vpx_00000000.png
rep jim clyburn georgia voting law jim crow sot sotu vpx_00000000.png
Now playing
02:13
Rep. Clyburn blasts GA voting law: It's the 'new Jim Crow'
Joe Manchin
CNN
Joe Manchin
Now playing
02:03
'I never thought in my life ...' Why Manchin won't walk away from bipartisanship
Gaetz speaks to members of the media outside the hearing Michael Cohen, former attorney and fixer for President Donald Trump, testifies at before the House Committee on Oversight and Reform at Rayburn House Office Building February 27, 2019 on Capitol Hill in Washington, DC. Last year Cohen was sentenced to three years in prison and ordered to pay a $50,000 fine for tax evasion, making false statements to a financial institution, unlawful excessive campaign contributions and lying to Congress as part of special counsel Robert Mueller's investigation into Russian meddling in the 2016 presidential elections.
Alex Wong/Getty Images
Gaetz speaks to members of the media outside the hearing Michael Cohen, former attorney and fixer for President Donald Trump, testifies at before the House Committee on Oversight and Reform at Rayburn House Office Building February 27, 2019 on Capitol Hill in Washington, DC. Last year Cohen was sentenced to three years in prison and ordered to pay a $50,000 fine for tax evasion, making false statements to a financial institution, unlawful excessive campaign contributions and lying to Congress as part of special counsel Robert Mueller's investigation into Russian meddling in the 2016 presidential elections.
Now playing
06:11
'Bombastic, antagonistic, unapologetic': A look at Gaetz's political career
Former House Speaker John Boehner attends a ceremony to unveil a portrait of himself on Capitol Hill, Tuesday, Nov. 19, 2019 in Washington.
Michael A. McCoy/AP
Former House Speaker John Boehner attends a ceremony to unveil a portrait of himself on Capitol Hill, Tuesday, Nov. 19, 2019 in Washington.
Now playing
02:42
Boehner says Republican colleague held 10-inch knife to his throat outside House floor
President Joe Biden, accompanied by Vice President Kamala Harris, and Attorney General Merrick Garland, speaks about gun violence prevention in the Rose Garden at the White House, Thursday, April 8, 2021, in Washington.
Andrew Harnik/AP
President Joe Biden, accompanied by Vice President Kamala Harris, and Attorney General Merrick Garland, speaks about gun violence prevention in the Rose Garden at the White House, Thursday, April 8, 2021, in Washington.
Now playing
02:05
Biden calls for ban on assault weapons
CNN
Now playing
02:22
Biden: High-speed internet is infrastructure
AFP/Getty Images
Now playing
03:24
Donald Trump breaks his silence on Matt Gaetz
CNN/WLOX
Now playing
01:43
'He says the quiet part out loud': Borger reacts to GOP election official's remark
AFP/Getty Images
Now playing
02:30
Haberman: Trump had to be talked out of defending Matt Gaetz
CNN
Now playing
03:26
Georgia's Lt. governor says elections law was a result of Trump's misinformation
(CNN) —  

Sen. Bernie Sanders on Monday released a decade of tax returns, providing new insight into how the Democratic socialist senator from Vermont became a millionaire between his two presidential runs.

According to returns provided by his campaign, Sanders and wife Jane’s bottom line jumped from $240,622 in 2015, the year he launched his first White House bid, to $1,073,333 a year later, as the once obscure lawmaker became a political sensation on the left and a bestselling author with royalties pouring in.

Since that first run, Sanders and his wife made a total of more than $2.79 million, putting them in the category of the super-rich.

Sanders in a statement said the returns “show that our family has been very fortunate.”

“I consider paying more in taxes as my income rose to be both an obligation and an investment in our country,” he added. “I will continue to fight to make our tax system more progressive so that our country has the resources to guarantee the American Dream to all people.”

The records show Sanders’ growing income and confirmed his status as a millionaire, largely on the strength of proceeds from book sales, including the bestselling “Where We Go From Here,” published with Macmillan in 2018.

Sanders reported a total 2018 family income of $566,421 – $382,920 of which came from writing and royalties. The documents showed he paid $137,573 in federal taxes in 2018 and owed $8,267 in taxes for the year. Sanders reported paying a 26% effective tax rate on his adjusted gross income. The couple reported donating $18,950 to charity.

Sanders last year made $110 in music royalties, presumably for his 1987 folk album, “We Shall Overcome,” and an additional $1,810 from his 1997 memoir, “Outsider in the House,” which was published by Verso. He was paid and additional $391,000 for his books.

Sanders had come under increasing pressure to make the tax disclosures as his primary rivals rolled out their own returns and critics – along with some allies – began to agitate for a more complete, public look inside the candidate’s pocketbook. The issue had become even more politically heated with Democrats continuing to demand President Donald Trump’s tax returns.

The Vermont independent made his records public on this year’s tax filing deadline, just ahead of an appearance at a Fox News town hall where he is expected to call on Trump to do the same.

The revelation that Sanders is now a millionaire had, in some quarters, surfaced doubts over his ability to effectively deliver the progressive populist message that made him a political star.

Sanders campaign manager Faiz Shakir brushed off those suggestions, telling CNN the candidate’s personal wealth had “zero impact” on his policies.

“If the ultimate question is, will he credibly push special interests and the billionaire class and the wealthy in this country to do the things that need to be done, like Medicare for All, like a climate jobs plan, the answer is yes,” Shakir said. “He could earn another million dollars and it would still wouldn’t matter.”

In 2016, during his first presidential campaign, Sanders released only one year of records – from 2014. Sanders recently revealed that his income from book sales in the aftermath of that race had made him a millionaire. Still, he remains one of the least wealthy members of the US Senate.

“Bernie Sanders paid his fair share of taxes,” Shakir said, adding that he hoped the returns would quiet the “hubbub and kerfuffle” that had grown in anticipation of its release. He also conceded that vague promises from Sanders and the campaign about their plans had contributed to the speculation. In multiple forums, including a CNN town hall shortly after he entered the race in February, Sanders pledge to share them “soon.

“I think there was some interpretation left to ‘soon,’ which I, in retrospect, would’ve loved to have alleviated by being a little bit more clear about when it was coming,” Shakir said. “We wanted to do 10 years and so we had (an internal) conversation saying, ‘let’s just do it all at once so we have the most recent one.’”