Joe Biden is beginning 2020 the same way he began 2019: a front-runner in a presidential primary race in which many expected him to flame out early, NBC News reports.

The former vice president has been attacked more by rivals and President Donald Trump than any other candidate in the race, and he’s arguably made more unforced errors than any other Democrat, but his position in the polls has not budged: He was averaging 29 percent in polls the day before he entered the race, and he's at 28 percent now.

"He's had the kitchen sink thrown at him," said former Virginia Gov. Terry McAuliffe, a Democrat who considered running for president himself but has instead helped fundraise for Biden. "Voters have seen all this information that's been thrown at him, and they've concluded that he is still the best person to beat Donald Trump."

Biden hasn't increased his support and is still relatively weak as a leading candidate. But he’s held steady atop a crowded field when other candidates who have climbed quickly have found it difficult to maintain momentum, and that might be enough for Biden to win.

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