Senate Minority Leader Charles E. Schumer (D-N.Y.) arrives to talk to reporters Tuesday on Capitol Hill. (Mark Wilson/Getty Images)

Senate Minority Leader Charles E. Schumer proclaimed confidence Wednesday in Democrats’ prospects in the midterm elections, while disclosing he had reached out to a major party draw for help — former president Barack Obama. 

In an interview with The Washington Post, Schumer (D-N.Y.) asserted that the number of states in which Democrats are playing defense has narrowed, though he declined to identify them. The Democrats are defending 26 Senate seats in November, including two held by independents who caucus with them, while the GOP has only nine seats on the ballot.

At the same time, Schumer dismissed any concerns about Sen. Robert Menendez’s surprisingly lackluster performance in Tuesday’s primary in New Jersey, in which a little-known Democratic primary challenger won nearly 40 percent of the vote while barely campaigning. 

Schumer declined to elaborate on specific Senate battlegrounds, instead arguing that the political thinking that favors Senate Republicans in the midterm elections is off-base and that the campaigns are much closer than expected.

“I think the conventional wisdom that it’s next to impossible or a steep climb is wrong,” Schumer said Wednesday in the interview. He continued, “If you look at each state’s public polling, you’d see much different results than the idea that it’s next to impossible.”

The Democratic leader said he has asked Obama to help the party try to retake the majority. 

“I've asked him to be involved in certain ways, and he’s been very amenable,” Schumer said. He declined to specify what he urged Obama to do, but an individual familiar with the discussion said Schumer has requested the former president’s help with fundraising. 

Obama has already waded into the battle for the Senate, endorsing Sen. Dianne Feinstein (D-Calif.) against her liberal primary challenger and raising money for Sen. Claire McCaskill (D-Mo.). As for campaigning directly with Democratic senators, Schumer said he would leave the decision up to individual candidates. 

Asked whether former president Bill Clinton and Hillary Clinton should campaign for Democratic candidates, Schumer declined to offer an opinion. 

“It’s up to each candidate if they want them or don’t want them,” he said.

Democrats are battling to regain control of the Senate but have been handicapped by a political map that largely favors Republicans, who now hold a 51-to-49 majority.

Ten Democratic senators are running for reelection in states that voted for Donald Trump in 2016, often by double digits, and Democrats have comparatively few areas to go on offense and take Republican seats. 

In the past six months, however, those 10 states have largely dwindled down to four remaining major battlegrounds where the polls show neck-and-neck races, Schumer said. He declined to identify those races. 

“When we started, in the 10 states that went for Trump where we have Democratic incumbents, about six months ago, three of them we said we’re nicely ahead,” Schumer said. “Doesn’t mean they’re foregone conclusions, but they’re no longer neck-and-neck races. And two months ago, we knocked off another three. So now there are only four of those left that are neck-and-neck.”

Democrats working to win the Senate majority have concluded that the four most worrisome states they have to defend are Florida, Indiana, Missouri and North Dakota. 

“We have very strong candidates, and they’re identified with their states,” Schumer said. “They have strong personalities, but their personalities are not just nice and charming and all nice. They are known as, you know, people who represent their states above all.”

In a recent interview with The Post, Senate Majority Leader Mitch McConnell (R-Ky.) recently highlighted the nine states he thinks will decide the battle for the majority: Arizona, Florida, Indiana, Missouri, Montana, Nevada, North Dakota, Tennessee and West Virginia. 

Schumer defended Menendez’s performance Tuesday, saying he did “just fine” in the primary. 

“Menendez works really hard for New Jersey, and when they find out that Mr. [Bob] Hugin embraces Trump and was an executive of a drug company that raised prices and got into all kinds of trouble . . . he’s not going to win that race,” Schumer said.