Former Vice President Joe Biden said Democrats can't afford to take the black vote for granted in 2020 the way they have in the past, as the Trump campaign ramps up its efforts to earn a larger share of voters in that demographic, according to The Hill.

Biden's campaign is struggling in recent weeks after poor showings in Iowa and New Hampshire — two states with relatively small black populations. The last potential claim Biden has to being the most electable candidate in the Democratic primary field is his popularity among black voters.

"You can't win — you can't take it for granted," Biden said of black support during an interview on NBC's "Meet the Press." "Last time we ran it was basically taken for granted. I'm the only one who has the record and has the background and has the support. They know me. They know who I am."

After finishing fourth in the Iowa caucuses and fifth in the New Hampshire primary, Biden has tried to convince supporters and donors to stick with him long enough for him to show his strength in more racially diverse states like South Carolina and Nevada.

Biden has held a significant lead in polls among black voters for most of the primary, but there is evidence that he's losing some of that support to other contenders, including frontrunner Sen. Bernie Sanders (I-Vt.) and former New York City Mayor Michael Bloomberg.

A Quinnipiac poll last week showed Bloomberg closing the gap with black voters, with 22% support compared to Biden's 27%. Sanders was at 19% with black voters.

President Donald Trump earned only 8% of the black vote in 2016, but is making a push to increase that support by highlighting criminal justice reform and a record-low black unemployment rate.

It may be unrealistic to expect a significant increase in black support for Trump. Black voters overwhelmingly default to Democrats in a normal year, and President Trump presents some unique challenges for the GOP in terms of reaching that group. But if the campaign is able to push that support into double figures, it could severely handicap the Democratic nominee's chances of victory.