Obama did throw his weight behind a quintet of governor candidates, backing Gavin Newsom in California, Jared Polis in Colorado, Stacey Abrams in Georgia, J.B. Pritzker in Illinois and Richard Cordray in Ohio.
If elected, Abrams would become the first female African-American governor in the nation. Pritzker is the brother of Penny Pritzker, who served as Obama's Secretary of Commerce, and Cordray served as director of the Consumer Financial Protection Bureau in the Obama Administration.
In a statement announcing the endorsements, Obama's office said that one of his priorities is to support candidates backed by the National Democratic Redistricting Committee, a group led by former US Attorney-General Eric Holder that aims to wrest control of the nationwide redistricting process away from Republicans.
Republicans seized on Obama's announcement, arguing that the absence of high-profile races on the list is a sign that those candidates are not clamouring for the former President's endorsement.
"I think this list is more interesting for the omissions than for the people he put on it," Republican National Committee Chairwoman Ronna Romney McDaniel said on Fox News. "People want President Trump's endorsement more than they want President Obama's."
President Donald Trump, like Obama, has declared himself eager to campaign, and he has already hit the trail for several candidates in tight primary battles. But his polarising statements and policies on trade and other issues have posed a dilemma for Republican candidates in moderate districts ahead of the Midterms.
A Pew Research Centre poll in July showed that 31 per cent of respondents said Obama has done the best job as president during their lifetime, compared with 10 per cent who said the same of Trump, who is less than halfway through his term.
