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Speeches before joint sessions of Congress tend to be forgettable. Even ones that make an impression rarely have long-term effects on politics or policy.

But there are exceptions. And as I listened to President Joe Biden give this year’s State of the Union address on Thursday night, I thought of one: a speech that then-President Barack Obama delivered to Congress in September 2009.

At the time, Obama was in the midst of an especially brutal political stretch, with his approval ratings sinking amid controversies over race and frustration that the economy wasn’t pulling out of recession. Worse still, his signature legislative campaign ― for a massive health care reform proposal ― was in deep trouble, with Republicans on the offense and conservative activists erupting at town hall meetings.

Many Democrats in Congress were ready to concede defeat. Obama didn’t want to let that happen, and he decided to make his case in person with a detailed, spirited address.

Two moments from that speech stand out. One came after Obama debunked a conservative talking point about his plan’s effect on undocumented immigrants. A lone Republican House member shouted out, “You lie!” That kind of heckling, so routine nowadays, was a serious breach of decorum back then. (If you don’t believe me, watch this clip of the reaction.)

The other moment came at the end of the speech, when Obama read aloud from a letter that former Sen. Ted Kennedy had written just before losing his battle with brain cancer, and that his widow subsequently sent to the White House. Kennedy, the Massachusetts Democrat who spent decades leading the fight for universal coverage, urged his colleagues to persevere even though he was gone.

The House member’s outburst was a sign of how angry Republicans had become about Obama’s health care reform effort, and how determined they were to stop legislation from passing. Obama’s invocation of Kennedy, the patron saint of liberalism, surely did nothing to change that.

But the primary audience for the speech wasn’t congressional Republicans, or any of their voters. It was the skittish Democrats who needed a reminder of who they were fighting for and who they were fighting against ― and, no less important, they needed reassurance that Obama could lead the crusade successfully.

“He didn’t have to move the public as a whole,” one White House adviser told me later. “He needed to move one hundred nervous people sitting in the room there with him.” He succeeded. Six months later, the bill, eventually called the Affordable Care Act, became law.

Fast forward almost 15 years to last night’s speech, with Biden facing a similar set of challenges ― not because he’s in danger of losing a fight to pass legislation, but because he’s in danger of losing his bid for reelection. It’s a more daunting challenge, given everything at stake this November. And this time it’s not just Democrats in Congress he needs to reassure. It’s also voters all across the country.

But this speech could still have a similar effect as Obama’s did in 2009. And I can think of a few reasons why it just might.

The Political Peril Biden Faces

Biden could use the lift. He currently trails Donald Trump, the former president and almost certain GOP nominee, by 1.8% in the RealClearPolitics polling average. That’s not a massive deficit, and the polling has all kinds of uncertainty baked into it ― plus, it’s still only March. But Biden is also behind in polls from several key swing states.

What makes Biden’s struggles so mystifying is that the underlying conditions would seem to favor his reelection. Friday brought yet another strong jobs report, with wages rising and unemployment near record lows. People are still struggling with lingering effects of pandemic-era price increases, but inflation has slowed dramatically, enough that consumer confidence is also on the rise again.

To these statistics, Biden can add a substantial record of legislative accomplishment, including initiatives on infrastructure, climate change and health care that are already having an impact on people’s lives ― by, for example, limiting how much seniors on Medicare have to pay in out-of-pocket drug expenses. Whatever the merits of these initiatives, whatever their real-world trade-offs, they have polling numbers that are off the charts. People love them.

Or at least they do when they hear about them. That’s one of Biden’s big problems: Many Americans simply aren’t aware of what he’s done, and so much of the public conversation has instead centered on his age and fitness for office.

On Thursday, Biden addressed those concerns directly with a few jokes and indirectly with a delivery that was by all accounts fiery and pugnacious. He repeatedly attacked Republicans, going after them over everything from their refusal to allow votes on bipartisan immigration reform to their ongoing antagonism toward Obamacare. And in what I thought was the night’s single most memorable moment, Biden directly ― if carefully ― called out the Supreme Court for rolling back reproductive rights.

The feisty energy was impossible to miss, as you can see from overnight headlines like “In-Your-Face Biden” (The New York Times), “Biden’s Blazing SOTU” (Semafor) and “Show of Strength” (CNN). (HuffPost’s splash headline was “Joltin’ Joe: Biden on Fire.”) Or just listen to conservatives like Fox News host Sean Hannity, who said Biden “sounded like a hyper-caffeinated, angry old man,” or Trump adviser Jason Miller, who described Biden as “partisan, bitter, unhinged, yelling.”

The Potential Moment Biden Can Seize

Those descriptions aren’t very charitable. They also aren’t what you say about somebody who lacks the vigor to serve as president. And although one energetic speech isn’t going to quell anybody’s doubts about whether Biden is fit to serve a second term, it could give him a chance to shift the focus of conversation ― away from questions about mental or physical acuity, and onto the substantive stakes of the election.

Biden on Thursday night did just that, touting his defense of abortion rights, his record and future plans on prescription drug prices, and his determination to shift more of the tax burden back onto the wealthiest Americans. In all of these cases, he was drawing clear lines between himself and his partisan adversaries, fully aware that ― as polls and recent elections have shown ― the majority of Americans are on his side of the divide, not theirs.

Not every issue breaks down so favorably, including two that Biden covered at length on Thursday: immigration and the ongoing conflict in Gaza. But in a conversation that’s more about Biden’s views and his record than his abilities, he can at least make a case for his approaches on both issues ― and why he thinks they put him closer to would-be supporters than Trump is.

No single event could transform the campaign, and the State of the Union address was no exception. But it may have increased the chances that Biden and his supporters can transform it on their own. And when you’re running a tough reelection campaign for president, that’s all you can ask.