Rep. Jim Himes leads a centrist bloc of Democrats who aren’t entirely happy with party leadership. (Cliff Owen/AP)

The leader of a centrist bloc of Democratic lawmakers expressed concern Friday that the party’s top three House leaders are in their late 70s, joining a chorus of younger Democrats questioning older leaders’ ability to overcome the party’s “generational gap.”

Rep. Jim Himes (Conn.), the chairman of the centrist New Democrat Coalition, told CNN that party leaders’ rising ages are a “problem” and declined to say whether he would support House Minority Leader Nancy Pelosi (D-Calif.) for speaker if Democrats take control of the House in the midterm elections.

“I have not made up a decision because I don’t know who’s running, so you’re not going to get a ‘yes’ or ‘no’ out of me today,” Himes told the network.

Acknowledging he is a “huge admirer of Nancy Pelosi’s operational ability,” Himes, 52, said Democrats will soon need leaders who can communicate effectively with younger voters.

“The fact that our top three leaders are in their late 70s — I don’t care who those leaders are — that is, in fact, a problem,” he said.

“We are at a moment in time where young people are involved as they never have been before,” he said. “I don’t care how good you are — there is a generational gap.”

Pelosi, 78, has said she intends to run for speaker if Democrats claim the House majority in November. Her deputies, Whip Steny H. Hoyer (D-Md.) and Assistant Leader James E. Clyburn (D-S.C.), are 79 and 78, respectively.

Clyburn made waves this month when he said he would be willing to serve as a “transitional” speaker should Pelosi not secure enough votes to win the speakership. “I’m very much up for it,” Clyburn, the No. 3 Democrat in the House, told McClatchy in an interview.

At least 45 Democratic lawmakers and congressional candidates have said they will not support Pelosi for speaker, according to a tally by The Washington Post. Several others, like Himes, have declined to give their view until after the election.

In response to criticism, Pelosi has defended her progressive credentials and noted her status as one of the country’s top female political leaders.

The issue has become a theme in House races around the country, as a growing number of progressive candidates distance themselves from the caucus’s longtime leader.

This week, the Democratic nominee in North Carolina’s Republican-leaning 13th congressional district said in a new television ad that she would not support Pelosi for speaker.

“I’ll vote against Nancy Pelosi for speaker, support term limits from party leaders, and I won’t take a dime of corporate PAC money,” Kathy Manning said in the ad.