Former President Barack Obama said during a campaign rally Monday that the current economic boom, which President Donald Trump has highlighted as a major victory for his administration, began with him.

"When you hear all this talk about economic miracles, remember who started it," Obama told the Nevada crowd, which responded with applause and cheers.

Obama, who was in Nevada supporting Democratic Senate candidate Jacky Rosen, reflected on his own administration, saying, "When I walked into the Oval Office 10 years ago, we were in the middle of the worst economic crisis of our lifetime, the last time the other party was in charge."

"I hope people notice," he continued, "that every time there is a pattern where they [Republicans] run things into the ground, we have to come back and clean things up."

"Nevada was hit as hard as any place [during the last recession]; everybody here remembers," Obama said, before joking about the young age of the attendees. "Not everybody," he clarified. "Because some of you were really young. Those of you who are older than 15 remember, sort of."

It wasn't the first time Obama has challenged Trump's claims to a driving a booming economy. In September, Obama told a crowd in Illinois to "remember" the current economic recovery began under his administration, the New York Times reported at the time.

After a long period of silence, Mr. Obama expressed his exasperation on Friday. "When you hear how great the economy’s doing right now, let’s just remember when this recovery started," he said in a speech kicking off a midterm campaign blitz. "When you hear about this economic miracle that’s been going on, when the job numbers come out, monthly job numbers, suddenly Republicans are saying it’s a miracle. I have to kind of remind them, actually, those job numbers are the same as they were in 2015 and 2016."

Trump responded to Obama's speech at the University of Illinois Urbana-Champaign by saying he "fell asleep" during it.

Obama further remarked Monday about what he characterized as some of his other accomplishments, saying his administration covered "20 million people on health insurance" and cut "our deficit by half," which he said was partly accomplished "by making sure the wealthiest Americans, folks like me, paid their fair share of taxes."

Obama also praised retired Sen. Harry Reid (D., Nev.), to cheers from the crowd. "The work we did, working with people like Harry Reid, who I love, we got the economy growing again," he said.

Rosen is running against incumbent Sen. Dean Heller (R., Nev.) in one of the country's most closely watched races. Heller is the only GOP senator up for an election in a state presidential candidate Hillary Clinton won in 2016. Despite the expectation Heller would lose in the midterms, polls show him to be neck-and-neck with Rosen.