Kamala Harris assumed office in historic fashion, becoming the first woman to serve "a heartbeat away from the presidency".

But her first year as vice-president has been far from a smooth ride.

Ms Harris' approval ratings have slumped.

While Mr Biden said in a press conference on Wednesday that he would keep her as his running mate if he stands for re-election, it remains to be seen whether that will put to rest speculation about her political future.

According to a November survey by USA Today, Ms Harris' public approval rating sat at 28%, making her one of the least popular vice-presidents in modern history - lower than Iraq War architect Dick Cheney, who was reviled by Democrats.

If Mr Biden's approval rebounds because Americans feel like those problems are being addressed, Mr Young said, her popularity will improve as well.

Since taking office, Ms Harris has been tasked with two high-profile assignments.

The number of immigrants crossing into the US from the "Northern Triangle" of El Salvador, Guatemala and Honduras surged during the first year of the Biden presidency, and the administration was looking for ways to stem the flow while reversing some of the more draconian policies of the Trump administration.

Mr Biden served a similar role as vice-president in the Obama administration.

It is probably no coincidence that Ms Harris' descent into negative approval ratings began when the whole of the immigration issue was hung around her neck.

Mr Biden has set his vice-president up to fail, thinks journalist and vice-presidential historian Kate Andersen Brower.

"I think that there is extra special focus on Vice-President Harris right now, because of the uncertainty around Biden, and whether he's going to run again," said Mr Young.

The vice-president's supporters attribute much of the criticism to racism and sexism against Ms Harris - the burden carried by the historic nature of her ascent to office.

Ms Hinds-English said she has ignored criticism of the vice-president.

In other words, all the problems Ms Harris has faced during her first year as vice-president also surfaced during her presidential campaign.

She's had a surprising amount of staff turnover in her first year in office, with her communications chief and press spokesperson both departing.

Ms Harris' problems have regularly been compounded by gaffes during one-on-one interviews and public appearances?

There are some indications that Ms Harris is doing so, as she has recently started spending more time at public events with Mr Biden, accepted more media interviews and hired a veteran communications operative.

Biden's first year in office - in six charts