Biden and Vice President-elect Harris will travel to Georgia to campaign on behalf of Democratic Senate candidates Jon Ossoff and Raphael Warnock starting this weekend.

Harris will be in Savannah on Sunday and Biden will visit Atlanta on Monday, the eve of the Tuesday runoff elections that will determine which party controls the Senate.

This is Biden and Harris’ second trip to Georgia ahead of the runoff. Biden will also be in the Peach State at the same time as Trump, who will be holding a rally on the same day to support Republican candidates Sens. Kelly Loeffler and David Perdue.

-ABC News' Molly Nagle

Just 16 days before he's set to leave office, President Donald Trump will headline a rally for Sens. Kelly Loeffler and David Perdue in Dalton, Georgia.

The rally comes on Jan. 4, the night before the two sitting senators face separate Democratic opponents -- Rev. Raphael Warnock and Jon Ossoff, respectively -- in two runoffs that could determine control of the Senate. The makeup of the Senate is currently projected to be 50 Republicans and 48 Democrats and left-leaning independents. If Warnock and Ossoff win, pushing the balance to 50-50, the Democrats would control both the House and Senate, due to Kamala Harris casting the deciding vote in the upper chamber.

Dalton is in Georgia's 14th Congressional District, which makes up the northwest corner of the state and is perhaps the state's most conservative district. Its congresswoman-elect, Marjorie Taylor Greene, has supported QAnon conspiracies in the past and has fully embraced, defended and perpetuated Trump's false narrative about the election.

The 14th Congressional District is also doing the worst of the 14 districts in terms of turnout for the runoff, according to Georgia Votes, which is analyzing the secretary of state's data.

Trump made his one and only appearance in Georgia during the runoff campaign on Dec. 5, when he spent nearly two hours ticking off baseless conspiracies about the presidential election and went on a tangent about how he didn't want to come to appear at the rally.

-ABC News' Quinn Scanlan

Continuing Biden and Vice President-elect Kamala Harris' focus on the worsening coronavirus pandemic Tuesday, the transition team announced nine additional members of the White House COVID-19 response team.

The new members will help focus on the "three crucial aspects of the COVID-19 response strategy: supply chain management, vaccinations, and testing," the transition team said.

"To recover from this pandemic, we must take aggressive action to manufacture, distribute, and administer vaccines, testing, and personal protective equipment in an equitable way. These individuals are deeply qualified and will restore public trust in the pandemic response by leading with facts, science, and integrity,” Biden said in a statement announcing the new members.

-ABC News' Beatrice Peterson

Following a meeting with his COVID-19 task force, Biden delivered remarks on the state of the worsening coronavirus pandemic and slammed the Trump administration for falling behind its goal in distributing vaccines to Americans.

"As I long feared and warned, the effort to distribute and administer the vaccine is not progressing as it should," Biden said. "If it continues to move as it is now, it's going to take years, not months, to vaccinate the American people."

The president-elected noted how officials working on "Operation Warp Speed," the federal government's vaccine program, had predicted this month 20 million vaccinations by the end of the year, but with just a few days left in 2020, the Centers for Disease Control has recorded about 2.1 million Americans as having received a dose.

"This will take more time than anyone would like and more time than the promises from the Trump administration have suggested. This is going to be the greatest operational challenge we've ever faced as a nation," Biden said. "And we're going to get it done."

Biden repeated his intention to invoke the Defense Production Act to compel companies in the private sector to accelerate the production of materials needed for vaccines and testing, as well as protective gear. He also announced that his administration will launch a public education campaign to promote vaccine acceptance and equity.

"We're also going to make sure vaccines are distributed equitably, so every person who wants a vaccine can get it no matter the color of their skin or where they live. We're going to ensure vaccinations are free of charge," he said.

Biden, overall, painted a bleak picture of soaring infections and deaths in the coming weeks, acknowledging the "grim milestone" of the U.S. crossing 330,000 deaths and saying the county may not see improvement until March. He implored Americans to wear a mask and social distance in the meantime -- and called on Trump to set an example.

"It would make a huge difference for President Trump to say 'wear masks.' I hope the President will clearly and unambiguously urge all Americans to take the vaccine once it's available," he said.

Biden and Vice President-elect Kamala Harris are participating in a virtual briefing with expert members of their national security and foreign policy agency review teams from the Queen Theater in Wilmington, Delaware, and taking the opportunity to draw stark contrasts between Trump's "America First" policy and their incoming White House.

At the top of the briefing, Biden praised the team for their work despite delays in the transition prompted by the Trump administration refusing to recognize Biden's ascertainment as the president-elect for more than two weeks.

"You’ve done it all under incredibly difficult circumstances, dealing with the COVID protocols, delays, delays in the ascertainments, and in a few cases obstruction from the current leadership," Biden said, thanking the group before taking aim at Trump's "go-it-alone approach" of the past four years.

“The truth is, the challenges we face today can't be solved by any one country acting alone. They demand American leadership. They demand cooperation with our allies and our partners. So I’m looking forward to hearing your assessments about the greatest challenges we may inherit and as we restore the principle of American leadership on the global stage -- which we have to and will do," Biden added.

After the briefing, Biden is slated to deliver afternoon remarks on the group's findings.

-ABC News' Molly Nagle