Resounding victories in Tuesday night's slate of state primaries and caucuses could put both President Joe Biden, a Democrat, and Republican Donald Trump, his predecessor in the White House, in possession of the required number of delegates for their respecitve party nominations.

Neither faces a serious challenge in contests across Georgia, Washington state, Mississippi, Northern Mariana Islands (Democratic primary) and Hawaii (Republican presidential caucuses), the Associated Press reports. The only question is whether Biden will reach the threshold of 1,968 delegates and Trump the 1,215 he needs to surpass the 50% national threshold to become their parties' presumptive nominees.

Biden has 1,868 pledged delegates entering the Tuesday primaries and Trump holds 1,078 delegates.

The rematch will mark the first between a sitting and former president since 1956.

Georgia was a pivotal battleground in the last presidential election — so close, AP reports, that Trump finds himself indicted there for his alleged push to "find 11,780 votes" and overturn Biden's victory. Biden won the Peach State by less than 12,000 votes four years ago and it is likely to be a major focus of both campaigns.

"Georgia has been ground zero on the national political landscape since 2018," Fred Hicks, a Democratic strategist based in Georgia, told CNN before Biden and Trump each held rallies there over the weekend. "It's appropriate that this would be the first major stop after the State of the Union where the president is restarting his campaign, and where Donald Trump is trying to regain momentum." 

But as both candidates seek to project strength in the key swing state, Biden and Trump are grappling with glaring flaws, the AP reports.

Trump is facing 91 felony counts in four criminal cases involving his handling of classified documents and his attempt to overturn the 2020 election, among other alleged crimes. He's also facing increasingly pointed questions about his policy plans and relationships with some of the world's most dangerous dictators. Trump met privately on Friday with Hungarian Prime Minister Viktor Orbán, who has rolled back democracy in his country.

The 81-year-old Biden is working to assure a skeptical electorate that he's still physically and mentally able to thrive in the world's most important job. 

He's also dealing with dissension within his party's progressive base, which is furious that he hasn't done more to stop Israel's war against Hamas in Gaza. Last month in Michigan, a related protest "uncommitted" vote attracted more than 100,000 votes and actually secured two Democratic delegates.