President Barack Obama Timothy Hiatt | Getty Images

Former President Barack Obama has been laying low when it comes to taking on President Donald Trump and the Republican Party. That’s not going to last much longer. The most high-profile member of the Democratic Party is expected to hit the campaign trail for House, Senate and gubernatorial candidates running in the midterm elections while getting guidance from House Minority Leader Nancy Pelosi, D-CA, and Senate Minority Leader Chuck Schumer, D-NY, according to three sources with direct knowledge of the matter. The timeline is fluid but the former president is expected to start making an impact in September, according to two sources familiar with his team's plan. One source close to Obama said his team has not decided when the former president will start campaigning or which districts he will focus on. A spokesman for Obama’s political operation declined to comment as did a representative for Pelosi. Schumer’s office did not return requests for comment.

Former presidents hitting the campaign trail is nothing new. After his last term in office, Bill Clinton traveled across the country to campaign rallies and fundraisers in an effort to bolster his party’s chances. Obama, however, is preparing to get involved with a midterm election that will require he and his associates to put their full weight behind candidates that have the best chance at winning, due to the uphill battle Democrats are facing in flipping both the House and the Senate.

Old networks, new campaign

Obama’s team is working with Organizing for Action (OFA) and the National Democratic Redistricting Committee (NDRC). Both the OFA and NDRC are led by former Obama aides. The OFA, a nonprofit organization that advocates for the Obama agenda through grassroots initiatives, is chaired by Jon Carson, the former director of the Office of Public Engagement. The NDRC focuses on redistricting reform and is run by former Attorney General Eric Holder. While his team hasn’t determined where it will make its first mark, the two Obama alumni groups published a map in early June of House districts they’re looking to target, which could be a guide to where the former commander in chief will land. The 27 districts include seven California seats that are either ranked as a toss-up or lean Republican, according to Larry Sabato’s Crystal Ball. Other notables are New York’s 11th district, where Republican incumbent Dan Donovan won a primary on Tuesday and is set to take on Democrat Max Rose, who has already received the backing of the Democratic Congressional Campaign Committee. Wisconsin’s first district, a seat held by Republican House Speaker Paul Ryan for over a decade, is another target. Donovan’s district is ranked as leaning Republican while Ryan’s is marked as a toss-up. The NDRC will also be on the ground to help Democrats running in governors races and for state legislatures. "The president and his team are in engaged in our work at the NDRC. They are working with our chair Eric Holder and our chair is working with them," a spokesman for the NDRC told CNBC. A spokesman for OFA declined to comment.

Obama aides already spending big

Obama’s former colleagues have been helpful in boosting certain Democrats’ campaign war chests. Priorities USA Action, a super PAC founded in 2012 by former Obama aides Bill Burton and Sean Sweeney with a dedicated midterm budget of $70 million, have already spent millions in Senate primaries to defend vulnerable Democrats. Federal Election Commission records show Indiana Senate incumbent Joe Donnelly received over $220,000 from the organization, which also spent $49,000 against his opponent Mike Braun. In Missouri, the group has so far spent up to $182,000 on behalf of Democratic Senator Claire McCaskill, while spending $142,000 against her opponent Josh Hawley. Their efforts have largely been focused on creating digital ads with $1.3 million going toward their production, according to the Center for Responsive Politics. Priorities USA and the House Majority PAC, a group dedicated to flipping the house from red to blue, have put together a $12 million program to help Democrats regain control of the House of Representatives.

Obama is a prolific fundraiser

Obama himself is also a prolific fundraiser. This week he is set to attend two money making events in California. On Thursday the former president will head to a gala for the Democratic National Committee in Los Angeles. The tickets start at $2,700 for general admission and $100,000 for premium seating. On Friday, he’s going to San Francisco to headline a luncheon fundraiser for the DCCC. He will be joined by Pelosi and Rep. Anna Eshoo, D-CA. The event will be hosted by Liz Simons and Mark Heising with tickets ranging from $10,000 to $237,300. Top democratic donors say Obama’s participation in the midterms is vital to the Democrats goal of defeating Republicans in November. “It is always important to have Barack and Michelle Obama on the campaign trail. In fact it is essential. They represent a politics of civility decency and accomplishment at a time when the country, at least in part, is looking to journey forward,” Robert Zimmerman, a veteran party donor, told CNBC. “So I think their presence will be critical in the election to have the Obama’s campaigning for Democrats,” he added. Republicans on the other hand, aren’t convinced that Obama working the campaign circuit will be enough to convince voters that Democrats are in the best position to lead the country. Josh Holmes, a former chief of staff to Senate Majority Leader Mitch McConnell, compared Obama helping Democrats to Hillary Clinton, Trump’s opponent in 2016, in that offering his assistance will only dampen their party’s enthusiasm and energize the Republican Party. “All things point to Democrats pushing for voter enthusiasm going into the election. The question is if Republicans are going to be replicate that and I can’t think of another motivating factor, other than Hillary Clinton, than Barack Obama,” Holmes said. “All of the economic anxiety that led to Republican majorities and the House and the Senate are embodied in Obama’s presidency,” he added.

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