WASHINGTON, Feb 7 (Reuters) - President Joe Biden pledged to work with the opposition party on Tuesday in a State of the Union speech that served as an olive branch to skeptical Republicans and a blueprint for his 2024 re-election bid.

In his first address to a joint session of Congress since Republicans took control of the House of Representatives in January, Biden was cited progress in a post-pandemic economy and stressed that a bitterly divided Congress could overcome its differences.

Speaker Kevin McCarthy, a Republican, sat behind Biden for the address for the first time.

"I look forward to working with you," Biden said at the start of his remarks on Tuesday night.

Biden, a Democrat, was expected to emphasize his offer to collaborate.

"To my Republican friends, if we could work together in the last Congress, there is no reason we can’t work together in this new Congress," he will say, according to excerpts released by the White House before the speech began.

One test of that challenge will be the White House push to raise the $31.4 trillion debt ceiling, which must be lifted in the coming months to avoid a default. The White House has said Biden will not negotiate over that necessity; Republicans want spending cuts in exchange for their support.

Seeking to project optimism ahead of a 2024 presidential campaign, Biden will say the economy is benefiting from 12 million new jobs, COVID-19 no longer controls American lives, and U.S. democracy remains intact.

"Today, though bruised, our democracy remains unbowed and unbroken," he will say, according to the excerpts.

Since his inauguration in 2021, shortly after the Jan. 6 attack on the U.S. Capitol, Biden has said he wants to unify the country. But he remains unpopular.

The president's public approval rating edged one percentage point higher to 41% in a Reuters/Ipsos opinion poll that closed on Sunday. That is close to the lowest level of his presidency, with 65% of Americans saying they believe the country is on the wrong track, compared to 58% a year earlier. Similarly, in the autumn of 2020, when Donald Trump was president, 65% of registered voters believed the country was on the wrong track, according to Reuters/Ipsos polling.

Arkansas Governor Sarah Huckabee Sanders, who once served as press secretary for Trump, rejected Biden's upbeat vision of the country in her Republican response.

“In the radical left’s America, Washington taxes you and lights your hard-earned money on fire. But you get crushed with high gas prices, empty grocery shelves, and our children are taught to hate one another on account of their race,” Sanders said in excerpts released ahead of her televised remarks.

Biden aides see the speech, which will draw millions of viewers and perhaps the president's largest television audience of the year, as a milestone ahead of the second presidential campaign he is expected to launch in coming weeks.

Biden turned 80 in November and, if re-elected, would be 82 at the start of a second term, a fact that concerns many Democratic voters, recent polls show.