It could also be seen as a bid by the former White House chief strategist to revive his own political fortunes.
Since May, Bannon has been paying his surrogates to produce political ads in cities across the United States, according to people with direct knowledge of the matter.
The campaign will tout the Trump administration's accomplishments that dovetail with Bannon's own America First views, including passing a comprehensive tax reform bill and working with Congress to curtail the Dodd-Frank Act's impact on community banks, people said.
The ads will argue that Trump needs Republicans to control the House and the Senate in order for him to continue to pursue his agenda, the people added. The ads will not endorse specific candidates but rather the need for Republicans to maintain control of both chambers.
The ads haven't been released, and it's unclear when voters will get a taste of Bannon's messaging. It also hasn't been determined whether the ads will be released on TV, digitally or on radio. However, the plan is to run them across the country, the people said.
As part of Bannon's plan, dubbed "top secret" by one of his allies, he's also looking to create a war room, a person with knowledge of the matter said, that will allow him to monitor contests through the November election.
It is unclear where Bannon is getting the financing. He has had a long history of working in media, politics and investment banking with wealthy individuals any of whom could be the source of funding.
Such campaigns usually cost tens of millions of dollars, experts said.
"For something like this, it's a multimillion-dollar operation. Let's say you target five to 10 states and you want to have a serious ad campaign for a month or two, you are looking at spending $10 million each month," said Bill Burton, former special assistant to President Barack Obama. "If it's successful, you usually scale up in spending."
A spokeswoman for Bannon declined to comment.
The effort is the latest example of Bannon trying to get back in the good graces of the White House.
He then returned to his post as executive chairman of conservative news outlet Breitbart News, where he vowed to keep boosting the president while vanquishing his enemies.
But his relationship with Trump took a bad turn in January, when author Michael Wolff published his tell-all book "Fire and Fury." In the book, Bannon called a meeting between Donald Trump Jr. and a group of Russians "treasonous" and "unpatriotic." He also claimed that investigators were "going to crack Don Jr. like an egg on national TV."
That was enough to get him pushed out at Breitbart, as one of its key financial supporters and an ally of Trump, Rebekah Mercer, turned on Bannon.
Her father, billionaire Republican donor Robert Mercer, also distanced himself from Bannon before the Wolff book was published.
A spokesman for Robert Mercer declined to comment. A spokeswoman for Rebekah Mercer did not return a request for comment.
While the Mercer family is no longer in his corner, Bannon still has allies on Wall Street who could be a source of funds for his latest political operation. He worked at Goldman Sachs in the 1980s and went on to start a boutique investment bank called Bannon & Co. with some Goldman colleagues.
Bannon continues to push his nationalist agenda around the world.
He recently toured Europe and met with candidates running for political office, including Italian populists who won the March elections and formed a coalition government in late May.
Bannon also is supporting Arizona Republican Kelli Ward, a hard-line conservative looking to keep retiring Sen. Jeff Flake's seat in GOP hands. A Real Clear Politics poll has her only one point behind the party's front-runner, Rep. Martha McSally, in the Aug. 28 GOP primary.
In past administrations, it's common for aides to depart and assist in either the midterms or presidential re-elections.
However, some political financiers and strategists from both parties looked at Bannon's effort with skepticism.
"I can never recall a time a former administration official who accused the president's son of treason, ran campaign ads in support of the administration," Democratic donor Robert Zimmerman said. "When the ad maker makes more news than the ad, you have a problem."
Josh Holmes, former chief of staff to Senate Majority Leader Mitch McConnell, R-Ky., isn't convinced anything will come of Bannon trying to publish ads in support of the president. He believes any effort to do so is an attempt by Bannon to gain notoriety of his own.
Bannon has been an outspoken critic of McConnell.
"If I'm betting, I bet nothing happens. I think there is no question that a guy like that yearns for attention in the national spotlight and he will do anything he can to regain that attention," Holmes said. "Ultimately the question you would have to ask is, is he trying to be helpful to the Republican Party, President Trump or to Steve Bannon? Usually, it's the latter category."