With the Senate in play and Democrats sensing gains in the House, White House aides say President Barack Obama will get more and more involved in down-ballot races as Election Day nears.

Until Thursday, Obama’s public campaign rallies have focused almost exclusively on making the case for Democratic presidential nominee Hillary Clinton and against her GOP opponent, Donald Trump. That changed, however, when the president flew to Florida and dove headlong into GOP incumbent Sen. Marco Rubio’s re-election fight.

The president cast Rubio as exclusively career-minded and harshly criticized the former GOP presidential candidate’s work ethic and intention to vote for Trump despite criticizing his party’s presidential nominee.

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“Unlike his opponent, he actually shows up to work,” Obama said of Democratic Rep. Patrick Murphy, Rubio’s opponent. Obama questioned how Rubio could vote for a person he once called a “dangerous con artist.”

White House Watch: ‘Big Guns’ Set to Hit Campaign Trail

Obama is scheduled to travel to Nevada and California on Sunday for events on behalf of Clinton and the party’s candidate for the Senate seat retiring Senate Minority Leader Harry Reid is giving up, Catherine Cortez Masto.

He’s held a list of private fundraisers for House and Senate hopefuls, but White House Press Secretary Josh Earnest on Friday said Obama intends to begin making public cases for more of his party’s congressional candidates.

“You will see the president as he travels make a forceful case not just for Secretary Clinton, although that’s his primary objective, but also to articulate his support for Democrats up and down the ballot,” Earnest said.

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The White House pegs the president’s coming congressional race campaigning on his popularity. A Gallup survey released Thursday put his approval rating at 55 percent; as recently as mid-April, it was in the 40s.

A RealClearPolitics average of several polls puts his approval numbers near 90 percent among members of his own party, and his stump speech is, in large part, a passionate plea to Democrats to go vote — and urge others to, as well — on Nov. 8. He often tells audiences at rallies to avoide wasting time jeering when he mentions Trump: “Don’t boo. Vote,” he advises at every stop.

“I think this is a testament to the deep reservoir of political goodwill and support that the president has, not just among Democrats across the country but among independents,” Earnest said.

Obama has filed a series of 30-second television ads for Democratic congressional candidates, which soon will begin playing across the country.

Contact Bennett at johnbennett@cqrollcall.com. Follow him on Twitter @BennettJohnT.