Presumptive Democratic presidential nominee Joe Biden will receive a helping hand from his former boss, President Barrack Obama, in an online fundraising event next week, to catch up with President Donald Trump’s campaign.

Biden announced on Monday, June 15, that he and the former president will hold “a grassroots fundraiser” next Tuesday, June 23, targeting tens of thousands of small-dollar donors.

An invitation obtained by Axios verified Obama for the event, which is the first reunion of Biden and the former president for a fundraiser.

In the invitation, Obama asked potential contributors to donate “any amount you can” for “the most important election of our lifetimes.”

The former president also asked for “Americans of all backgrounds and political stripes to join together” to vote for Biden as a way to rebuild the economy and expand health insurance coverage.

Obama also told supporters that, with a vote for Biden, they “should have the chance to make of our lives what we will.”

Obama’s participation with Biden in the fundraiser marks the ramping up of the former president’s engagement to try to defeat President Trump, according to Axios.

The former president endorsed Biden in April, but his endorsement came after Sen. Bernie Sanders (I-Vt.) dropped out the White House’s bid, leaving Biden with no competitor.

Biden’s campaign and the Democratic National Committee (DNC) together raised $80.8 million in May, their single best month of fundraising for the 2020 cycle, The Hill reported Monday. In April, Biden and the DNC raked in about $60.5 million.

President Trump’s campaign and the Republican National Committee (RNC) have not announced their fundraising numbers for May. In April, Trump and the RNC raised $61.7 million, narrowly beating out Biden and the DNC.

The Trump team ended April with a massive cash-on-hand advantage, reporting more than $255 million cash on hand, compared with the approximately $100 million of Biden team.

On President Trump’s birthday on June 14, his campaign and the RNC brought in $14 million, marking their largest online fundraising day ever.