Merrick Garland, Biden's pick for attorney general, could face tricky political questions during his confirmation hearing before the Senate Judiciary Committee today. In the wake of the Jan. 6 attack on the Capitol, Garland and Democrats are expected to point to Garland's work prosecuting the Oklahoma City bombing as evidence of his ability to investigate and prosecute domestic terrorism.

"If confirmed, I will supervise the prosecution of white supremacists and others who stormed the Capitol on January 6 – a heinous attack that sought to disrupt a cornerstone of our democracy: the peaceful transfer of power to a newly elected government,” Garland will say.

Garland's opening statement also conveys a commitment to equity, saying that upholding the Civil Rights Act remains "urgent" for the Department of Justice. Garland has received ample bipartisan support, ahead of his confirmation hearings before Senate Judiciary Monday and Tuesday, 61 former federal judges and a bipartisan group of more than 150 former Justice Department officials have penned letters in support of Garland's confirmation.

-ABC News' Alexander Mallin and Benjamin Siegel

Biden and Harris will participate in an event Thursday afternoon commemorating 50 million COVID-19 vaccine shots administered during the Biden administration, which is halfway to Biden’s goal of distributing 100 million COVID-19 shots in his first 100 days in office.

When Biden set out the goal at the beginning of his term, the administration was already on pace to administer nearly 1 million vaccines a day, which some public health experts have said is not fast enough to control the pandemic.

Dr. Anthony Fauci, Biden’s chief medical adviser, has estimated that 325 million people will need to be immunized for the pandemic to end and to reach that threshold, Biden would need more vaccinations.

Biden has rejected the suggestion that his goal was too low, telling reporters in January that, "it's a good start."

Meanwhile, Harris visited a Giant supermarket in Southeast Washington, D.C. Thursday morning to promote the administration’s Federal Retail Pharmacy Program for COVID-19 vaccinations, which has delivered 1 million doses to over 6,500 pharmacies across the country.

Harris spoke to the store's pharmacist and then watched as a patient, Brenda Thompson, received her second dose of the Moderna vaccine.

Biden will also participate in the National Governors Association’s Winter Meeting Wednesday afternoon, and the White House will give a press briefing at 12:30 p.m.