Updated

If President Obama didn't have enough on his plate already, he's now thrust himself into the middle of a statewide race that has sparked growing resentment among some New York Democrats.

Sens. Chuck Schumer (D-N.Y.) and Bob Menendez (D-N.J.) asked Obama to implore Rep. Steve Israel (D-N.Y.) against challenging New York Sen. Kirsten Gillibrand in the Democratic primary next year, FOX News has learned.

Israel was poised to announce his candidacy until the president intervened with a Friday afternoon phone call in an effort to clear the field for Gillibrand, a source told FOX News, calling the move "messy."

"This is a tough, heartfelt decision for me. I have received encouragement to pursue this fight from all corners of our great state," Israel said in a statement.

The senators solicited Obama's assistance to help Gillibrand avoid a competitive primary in 2010, a Democratic New York source told FOX News.

Menendez heads the Democratic Senatorial Campaign Committee, the panel charged with electing party members to the Senate and led by Schumer in past years.

It's rare for a president to inject himself into statewide politics. And a host of New York political insiders with ties to several House Democrats say they're angry that the president even got involved.

"What? You can't have a primary? It's decided in backroom deals?" asked a source who spoke to FOX News on the condition of anonymity. "What if someone told Obama he couldn't have a primary and Hillary (Clinton) would just be the nominee? Where would he be? It's an outrage."

Gillibrand's appointment to the Senate has been controversial from the start. Many New York House Democrats were appalled that Gov. David Paterson tapped such a junior lawmaker to succeed Clinton in the Senate when she became secretary of state. Upstate New York voters first elected Gillibrand to the House in 2006 in an upset and Paterson appointed her to the Senate a little more than two years later.

Even New York Rep. Carolyn McCarthy warned that she would challenge Gillibrand in the Democratic contest before Paterson appointed her. Others have questioned whether the moderate Gillibrand would be viable in a statewide race.

Despite speaking with Israel, Obama did not make similar requests of other potential Gillibrand challengers such as McCarthy, and New York Reps. Carolyn Maloney or Rep. Jose Serrano.

"I can't imagine why (Obama) would do this," said one source, referring to the president's request to Israel to step aside. "I am sure that it will upset many (New York) delegation members."

In a statement, Menendez praised Israel as a "terrific Congressman" and said his panel looks forward to continuing working with (Gillibrand) to make sure she well-prepared for her race."

McCarthy, Maloney and Serrano all declined comment for this story.