Joe Biden cracked jokes about President Donald Trump’s tweets. Cory Booker declared Georgia a “blue state.” Beto O’Rourke unveiled his voting rights plan. And Pete Buttigieg visited hallowed Democratic ground.

Four leading presidential candidates converged on Atlanta on Thursday to court voters, meet with activists and raise a boatload of campaign cash.

And while they all had different priorities and target audiences during their visits, they each carried the same message: Georgia will be no afterthought in the 2020 election. It's a sure-fire battleground state.

“What we need to do is get people out to vote,” said Booker, a New Jersey U.S. senator. “This is a blue state. What that means is we need to go back to organizing and build a 50-state party.”

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Not surprisingly, Republicans beg to differ. They’ve swept every statewide election since 2010, and Republican presidential candidates have carried the state in every vote since 1996.

The state GOP greeted Booker’s insistence that Georgia is a “blue state” with a biting reminder of Republican Brian Kemp’s victory in November.

“Yeah Spartacus, just like Stacey Abrams is ‘governor,’ ” the party said on social media.

Georgia is indeed getting more early attention from presidential candidates than it has in decades, with more than a dozen visits from the top contenders since January. And they’re not solely focusing on Atlanta. The contenders have crisscrossed the suburbs, made pilgrimages to Plains and visited Augusta.

They’re engaged early in part thanks to Georgia’s trove of 120 delegates that will come in handy at next year’s nominating convention. But it’s also because the tight 2018 elections convinced them that Georgia is up for grabs.

Democrats last year picked up a spate of legislative seats in Atlanta’s suburbs, forced two statewide races into runoffs and, in the premier contest, got Abrams within 55,000 or so votes of defeating Kemp. And so, on a rainy Thursday, four candidates arrived with dreams of outdoing Abrams next year.

Two of the candidates, Booker and Buttigieg, tried to impress a crowd of veteran strategists at the African-American Leadership Council Summit in downtown Atlanta. Biden and O’Rourke headlined a glitzy fundraiser for the national party in Buckhead.

And in between, each of the four tried to make a blitz of connections with party leaders and activists at a frenzy of fundraisers and events.

Booker, who refers to himself as a “junk-food vegan,” appeared at a barbecue and tofu fundraiser. Buttigieg held court with a small group of donors at Manuel’s Tavern, a must-visit for generations of Democratic candidates.

A crowd of selfie-takers surrounded O'Rourke at Krog Street Market hours after he held a town hall at the Old Lady Gang soul-food palace. And Biden held court at a fundraiser at an Ansley Park mansion, where a coalition of Democrats from the party's heyday mixed with younger rising stars.

The new Ohio?

It was an Atlanta debut for both Buttigieg and O’Rourke, who don’t boast the same network of support in Georgia as many of the other candidates. They tried to make the most of their time here.

In a nod toward the voting rights issues that dominated the race for governor, O'Rourke unveiled a plan that aims to register 50 million more people by 2024, make Election Day a federal holiday, abolish voter ID requirements and set new term limits on U.S. Supreme Court justices and members of Congress.

“As I watched what happened in Georgia … I saw the lines that stretched hours long, voting machines that didn’t work … and the implication that some people weren’t intended to vote,” said the former Texas congressman, who lost his challenge last year against Republican U.S. Sen. Ted Cruz.

He added: “Texas and Georgia — they’re not red states. They’re nonvoting states.”

Before a few dozen donors at Manuel’s, Buttigieg asserted that his experience as mayor of South Bend, Ind., and his left-leaning positions on an array of issues will help him attract even the most jaded of voters.

Otherwise, he warned, Trump can prevail again if Democrats nominate a status quo candidate who “looks like we are preserving the system.”

Later, speaking to hundreds of black leaders, he challenged the party to invest and organize in Georgia to capture its 16 electoral votes for the first time since Bill Clinton’s election as president in 1992.

“We invested in Ohio and not so much in Georgia last time, and we saw actually the results suggested Georgia is no less within reach,” he said. “Part of that is demographics, but a lot of it is organizing.”

‘Own the 21st century’

Booker stepped up his criticism of the state’s new anti-abortion “heartbeat” law, which has attracted a chorus of opposition from Democratic presidential candidates.

Speaking to a crowd of mostly black activists, he called the new restrictions an “anti-democratic” law and an assault on low-income women and minorities who lack health care options.

“I think a lot of people are going to be working to change that,” he said. “But I think until then, nobody should be silent on this issue. I think that silence is tantamount to complicity.”

And he issued a plea to Democrats to ramp up efforts in Georgia to organize and register voters — particularly residents in “overlooked” communities who are less likely to participate in elections.

For Biden, the former vice president, Thursday’s visit offered a chance to reconnect with the deep network of supporters he cultivated over decades in public office. And he showcased those ties at a fundraiser at the home of Mack Wilbourn, an airport concessionaire.

While most Georgia Democrats haven’t picked sides, Wilbourn’s two-story den was packed with some of the party’s most prominent figures in the state.

Former U.N. Ambassador Andrew Young and ex-Gov. Roy Barnes caught up with old friends, while a few feet away Atlanta Mayor Keisha Lance Bottoms chatted with well-heeled donors. U.S. Senate candidate Teresa Tomlinson, a former Columbus mayor, was front and center.

Biden spoke for about 30 minutes as the crowd noshed on gourmet sandwiches and pastries. He talked of his decision to enter the race and his worry, on the 75th anniversary of D-Day, that NATO will “be disintegrated” if Trump wins again.

He added, with a sigh, that Trump is “tweeting about Bette Midler” while overseas to honor the war dead. And he remarked, with sarcasm, that it “really worries me” that both Trump and North Korea dictator Kim Jong Un have criticized him.

Before Biden bolted to the next event, he told the group that the U.S. could be poised to “own the 21st century” if the country can pull together and cease the partisan infighting.

“If we continue to treat the other team like they’re the enemy and not the opposition, how are we going to get anything done?” Biden asked.

“I’m not joking — I’m deadly serious,” he said. “If we don’t change who we are, our kids will inherit a country that will take a long time to get back on track.”

Stay on top of what’s happening in Georgia government and politics at www.ajc.com/politics.