(CBS) — Former President Barack Obama launched his return to the political arena, two months before the midterm elections, blasting Republicans for “the politics of division and resentment and paranoia.”

He said the party has passed a massive tax cut for rich people who don’t need it and allowed the Trump Administration to exit the global climate change agreement and cozy up to Russian leader Vladimir Putin.

“What changed? … What happened?” in the Republican Party, he asked.

Obama gave a speech Friday at the University of Illinois and is hitting the campaign trail for his fellow Democrats, with an event in California for House candidates and then a stop in Ohio next week.

He also took direct aim at President Trump.

He said this election is critical in American history and urged citizens to push back against those who appeal to anger, fear and resentment.

The greatest threat to American democracy, the former president said, is not Donald Trump, Republicans in Congress, the Koch brothers, too much compromise from Democrats, or Russian hacking — the greatest threat to American democracy is cynicism that keeps Americans from participating in the democratic process, he said.

“As a fellow citizen, not as an ex-president but as a citizen, I’m here to deliver simple message and that is that you need to vote because our democracy depends on it,” Obama said.

“Just a glance at recent headlines should tell you that this moment really is different,” he added. “The stakes really are higher. The consequences of any of us sitting on the sidelines are more dire.”

After the speech, RNC spokeswoman Ellie Hockenbury said in a statement: “President Obama is still dismissing the millions of voters across the country who rejected a continuation of this policies in favor of President Trump’s plan for historic tax cuts, new jobs and economic growth. Democrats may have a new resistor-in-chief on the campaign trail, but they’ll need more than a message of resist and obstruct to win this November.”

Trump, meanwhile, claims he fell asleep watching Obama’s speech.

“I’m sorry, I watched it, but I fell asleep,” Trump said at a campaign appearance in Fargo, North Dakota. “I found he’s very good for sleeping.”

 Contributing: CBS News