Sen. Bernie Sanders said he will not be seeking Hillary Clinton's advice along the 2020 campaign trail.

"She has not called me," the Vermont senator said of Clinton during an appearance on ABC's "The View," adding that they have "fundamental differences."

Sanders also rejected the notion he's part of the reason Clinton lost in 2016, noting he campaigned all over the country for her.

When asked why he thought Clinton lost, Sanders said Clinton probably should've engaged more with working class voters.

Sen. Bernie Sanders on Friday said "I think not" when asked if he'll be seeking former Secretary of State Hillary Clinton's advice for his 2020 presidential campaign.

"She has not called me," the Vermont senator said of Clinton when pressed on the subject by host Meghan McCain during an appearance on ABC's "The View."

Sanders said although Clinton is one of the most influential figures in modern US history, it's clear that they have "fundamental differences."

The senator shocked much of the political world in 2016 when he gave Clinton a run for her money during a contentious primary campaign. Sanders ultimately lost to Clinton, endorsed her, and went on to campaign on the former secretary of state's behalf nationwide.

But some of Clinton's most fervent supporters and former staffers still seem to feel Sanders should've dropped out of the race earlier and point to his insistence on running until the final primary as one of the reasons she ultimately lost to President Donald Trump in the general election.

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Addressing this on his appearance on "The View," Sanders said, "Those criticisms come from our political opponents. The answer is that I knocked my brains out working to get Hillary Clinton elected president. I went all over this country."

He also said his critics should consider the fact he received more votes from young people during the primary season than Clinton or Trump combined. "We brought a lot of young people into the process," Sanders said.

Sanders was also questioned on why he thought Clinton lost to Trump.

He expressed a reluctance to rehash the previous election, but added, "In some ways, she didn't reach out to working class people in the way I think she should've. There were states where she didn't campaign as vigorously as she should've."

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When Sanders was questioned on why he wasn't successful the last time around and what will be different in 2020, he said, "This time it'll be stronger, we'll be involving more people, it’ll be more diverse, and most importantly, this time, we're gonna win."

And to those who think Sanders, 77, is too old to run for president, he said, "Judge people on the totality of their lives ... Judge people on the work that they do."