Democrats are increasingly nervous that controversial New York City Councilman Charles Barron could be central Brooklyn's next congressman.

Barron is a candidate in the June 26 party primary to replace retiring Rep. Ed Town. The incumbent endorsed Barron last week in a move that rattled the New York congressional delegation.

Barron, a former Black Panther, is known for a litany of controversial statements.

He has called Israel "the world's greatest terrorist," compared Gaza to a "concentration death camp," and described Libyan dictator Moammar Gadhafi and Zimbabwe President Robert Mugabe as "heroes."

At a 2002 rally for slave reparations, he said, "I want to go up to the closest white person and say, ‘You can't understand this, it's a black thing' and then slap him, just for my mental health."

Members of New York House delegation have endorsed Assemblyman Hakeem Jeffries.

Rep. Jerrold Nadler, D-N.Y., and a coalition of Jewish groups held a press conference Monday discouraging voters against Barron's candidacy, calling him "anti-Semite."

Sen. Kirsten Gillibrand, D-N.Y, who is up for reelection in November, also threw her support behind Jeffries after taking issue with Barron's position on Israel.

BuzzFeed also noted that the White House implicitly backed Jeffries at a New York City fundraiser two weeks ago when the candidate had a photograph taken with President Obama and former President Bill Clinton.

And in a strongly worded editorial on Sunday endorsing Jeffries, The New York Daily News described Barron as a "malignant clown."

Some Democrats worry privately that Barron could emerge as their own version of conservative flame-thrower Rep. Allen West, R-Fla.

West is known, among other statements, for estimating that "78 to 81" Democrats were communists and for telling Democratic National Committee Chairman Debbie Wasserman Schultz in an scathing email that she was "not a lady."

But endorsements from Towns and the local AFSCME affiliate have fueled Barron's campaign, even he has far less cash and establishment support than Jeffries.

Towns's backing was particularly surprising to many political handicappers since Barron mounted a heated primary challenge against the incumbent in 2006.

Voter turnout for the primary is expected to be low. But whoever emerges as the winner is expected to cruise to victory in the November general election.

Cristina Marcos contributed to this report.