Sen. Charles Schumer (search) will become a leader in the Democratic Party's national effort to regain momentum -- abandoning a possible run for governor in 2006, his office said Monday.

Schumer, D-N.Y., agreed to head the Democratic Senatorial Campaign Committee (search) and take a seat on the powerful Finance Committee, giving up his anticipated 2006 gubernatorial campaign, a race which could have pitted him in a primary against state Attorney General Eliot Spitzer (search).

Schumer, fresh off a record-setting re-election win, phoned incoming Senate Minority Leader Harry Reid Sunday night to accept the offer.

"In short, this was an offer that, for the sake of New York, I could not refuse," Schumer said in a statement. "I called Senator Reid last night, telling him I had accepted his offer along with its concomitant commitment that I see the DSCC job through the 2006 election and run for no other office."

Schumer said Reid pledged that the new job would also come with added responsibility for shaping the day-to-day message of the Democratic party.

"Last week, I was offered a once-in-a-career opportunity that would allow me to serve even more fully the state and the country I love," Schumer said.

The Finance Committee oversees tax policy, affecting Social Security (search), Medicare (search) and Medicaid (search).

"These will be crucial, battleground issues in the upcoming Congress and decade," the senator said.

Reid's offer also allows Schumer to keep his seat on the Judiciary Committee at a time when the panel is expected to see some of the most important political maneuvering of the second Bush administration.

Bush may end up nominating several new justices to an aging Supreme Court, including the chief justice position, and Democrats on the panel would play a major role in any effort to block nominees they claim are too conservative.

The national party's clock did not give Schumer much time to decide on the governor's race. He had refused to rule out a run for governor in 2006, but the DSCC position and committee posts are being assigned this week as Congress returns for a lame duck session.

Schumer won a second term in a landslide Nov. 2, winning 71 percent of the vote, more than any other senator in New York's history.