The appearances also show how important Georgia and Iowa have become in 2020. Neither state is a key to Biden’s main paths to defeating Trump in the Electoral College, but wins in either state would dramatically boost Democrats’ chances of taking the Senate. Winning both states would likely guarantee it.

“He's coming to Georgia because he can win and these Senate races are absolutely in play,” said Sarah Riggs Amico, Democratic nominee for lieutenant governor of Georgia in 2018. “If we win both of these Senate seats in Georgia, it's almost mathematically impossible for Mitch McConnell to remain majority leader.”

Biden made the pitch directly in Atlanta at a drive-in rally featuring 365 cars and nearly 800 people, after Ossoff and Warnock had both already addressed the crowd.

“I can’t tell you how important it is that we flip the United States Senate. There's no state more consequential than Georgia in that fight,” the former vice president and 36-year Senate veteran said.

Biden’s camp said this spring that it would keep as many options as possible on the table as it sought 270 electoral votes, and the campaign stressed again this week that Biden’s trips are scheduled with winning the presidency chiefly in mind, not just making excursions to boost Senate hopefuls.

“If we didn’t think we were competing in Georgia we wouldn’t be sending Joe Biden there a week before the election,” one adviser said.

But they acknowledged that the Senate races did play into the late trips to Georgia and other surrogate travel over the final week before Election Day. “It’s always been on our mind and it’s always been something that we have factored in,” the adviser said.

Biden’s campaign schedule — which has remained limited out of both caution and confidence — has focused most heavily on Pennsylvania, but he’s also traveled to Arizona, Michigan and North Carolina, all of which also have competitive Senate races. Democratic Sen. Gary Peters appeared with Biden at a rally this month, but Cal Cunningham in North Carolina and Mark Kelly in Arizona didn’t join events in those states.

As Biden faced challenges from the left in the presidential primary, he argued repeatedly that he would have the most appeal and create the best conditions for down-ballot Democrats in tough states and districts. Most Democrats in competitive races have rejected "Medicare for All" in favor of a public health insurance option and support other measures fighting climate change instead of the "Green New Deal," aligning them more closely with Biden.

Georgia and Iowa weren’t considered to be part of Democrats’ likeliest paths back to a Senate majority after 2018. Georgia has two races, but the state’s runoff rule requiring a majority of the vote to win makes it a taller hurdle than some other states. The campaign between Ossoff and GOP Sen. David Perdue is highly competitive, and Warnock is likely to finish first in the special election before likely heading to a Jan. 5 runoff.

Stewart Boss, a spokesperson for the Democratic Senatorial Campaign Committee, said the fact that these states were battlegrounds showed Democrats are "in a strong position firmly on offense in the closing days."

Biden didn’t mention the Republican contenders in the special election in his remarks, but he jabbed at Perdue for his mispronunciation of Sen. Kamala Harris’ name at a Trump rally a few weeks ago, telling the endangered Republican that it’s “gotta stop.”

John Burke, a spokesperson for Perdue, said in a statement that Biden has “spent nearly five decades in government and has absolutely nothing to show for it,” and said Perdue was proud of his work with Trump for the state.

Iowa has seen steady investment from Democrats, and party nominee Theresa Greenfield has consistently polled even with GOP Sen. Joni Ernst since the Democratic primary early in the summer. Biden’s standing in the state Barack Obama carried twice before Trump’s 2016 win has been a major boost.

“The fact that he is coming here just emphasizes the fact that this is a critical Senate race and that this is a state that he has a good shot of winning,” said Scott Brennan, a former state Democratic Party chair. “Six months ago we would have laughed at that and now we think he has a real shot here.”

Greenfield said it was “exciting” that Biden was coming to Iowa, according to audio of her remarks, saying it suggests the state is a true battleground. But she is on an RV tour this week and it wasn’t clear as of Tuesday whether she would join Biden’s campaign event.

Meanwhile, Ernst joined Trump at a campaign rally across the border Tuesday night in Omaha, Neb., where the local media market includes parts of southwestern Iowa. Ernst's campaign also hit Greenfield by saying Biden's visit showed she "stands with the liberal policies" he's running on.

Doug Gross, a veteran Republican operative in Iowa, said the top of ticket and Senate races were tied together and both sides would get a boost of attention from the visits. But Trump has visited the state several times, and this is Biden’s first foray.

“It’s a twofer for him,” Gross said. “He's helping himself with six electoral votes that otherwise wouldn't be play, and potentially getting himself a majority in the Senate, so that's a smart move.”

Biden isn’t broadly seen as a bogeyman for moderate voters, and his image is featured far less often in Senate TV ads than progressive Democrats. But Republicans still hope to get some juice out of tying candidates together.

“Biden has joined Chuck Schumer in calling for radical change by way of eliminating the filibuster and packing the court with liberal justices,” said Jesse Hunt, a spokesperson for the National Republican Senatorial Committee. “Candidates loath to answer for the threats will now have no choice but to confront it head on.”

Democrats, meanwhile, are tying Trump and Republican senators together. At her event with Jill Biden in Maine, Gideon said Trump has been “enabled and emboldened” by the GOP Senate and Collins.

"With a blue Senate, Joe is going to be able to do so much more to get our country back on track,” Jill Biden said, calling Maine “critical.”

Annie Clark, a spokesperson for Collins' campaign, in a statement criticized Gideon for not doing enough in the legislature on Covid-19 response, accusing her of having been “inexcusably on the sidelines” to campaign.

While Maine and Iowa have been core Senate races for both parties for months, Warnock, in a brief interview, said Biden’s trip to Georgia was evidence that “the folks at the national level are responding to what's going on here on the ground.”

Biden himself marveled at the competitive nature of the state in his remarks.

“We win Georgia, we win everything,” Biden said.