New York Sen. Charles Schumer (D) donated another $500,000 to the Democratic Senatorial Campaign Committee earlier this week, bringing his total donations to the party’s campaign arm to $2.5 million for the cycle.

Illinois state Sen. Barack Obama (D) also continued his generosity to the DSCC, giving $50,000 in direct contributions and another $50,000 to state parties on Tuesday.

Obama is considered a shoo-in to replace retiring Sen. Peter Fitzgerald (R-Ill.) on Tuesday. The Republican nominee is former presidential candidate Alan Keyes.

“I don’t think this organization can thank Senator Schumer, Barack Obama and all of the Senators and candidates who have helped us out enough,” said DSCC Communications Director Brad Woodhouse.

The contributions from the two men come just days before the November election and provide a cash infusion to the DSCC as committee officials make final spending decisions.

Much of the money is likely to be disbursed in Kentucky and South Dakota, for two races that have tightened in recent days.

The contributions also cement talk that Schumer and Obama are the two leading candidates to chair the campaign committee in the next cycle.

Current DSCC Chairman Jon Corzine (N.J.) cannot serve a second term because he is up for re-election in 2006 — and is also considered a likely candidate for Garden State governor in 2005.

Schumer’s largess is merely a drop in the bucket of the $16.8 million he had on hand at the end of September.

The New York Senator has raised more than $26 million for his re-election race against unheralded state Assemblyman Howard Mills (R).

Schumer is regularly mentioned not only as a potential chairman of the DSCC but also a candidate for governor next cycle.

In an interview with the Journal News of Westchester County on Tuesday, Schumer said that “‘governor’ is not on my radar screen.”

Contrary to published reports earlier this week, Schumer has not established a new state party committee aimed at funding a potential gubernatorial bid. Due to Empire State law, Friends of Schumer, the Senator’s federal campaign committee, had to file a separate registration in New York for Schumer to donate more than $1,000 to local candidates. He has given roughly $500,000 to state and local candidates so far this cycle. The committee registered in New York is the same campaign account that Schumer has long held in Washington, D.C.

Under a little-noticed ruling by the Federal Election Commission in March, no federal official can directly transfer funds from a Senate account into a gubernatorial account.

Schumer could, however, donate heavily to the state party from his Senate account with the understanding that the transferred money would be spent on his gubernatorial race.

Meanwhile, Obama continued to ensure that his arrival on Capitol Hill will be met with rampant speculation about his future ambitions.

Aside from his $50,000 contribution to the DSCC, he sent $12,500 to the Nevada

Democratic Party, $12,500 to the Kentucky Democratic Party, $10,000 to the South Dakota Democratic Party, $5,000 to the Georgia Democratic Party and $10,000 to Florida Victory, a coordinated effort to help the Senate bid of former state Education Commissioner Betty Castor (D).

Late last month, Obama raised and contributed a total of more than $500,000 for Democratic candidates and causes, including $100,000 that went to the DSCC.

In addition, Obama recently wrote two fundraising e-mails for the liberal organization MoveOn.org that netted $1.2 million for seven Senate candidates around the country, including $185,000 that went to the newly competitive campaign of state Sen. Dan Mongiardo (D), who is fighting a fierce battle with Sen. Jim Bunning (R-Ky.).

Mongiardo held a Chicago fundraiser this week that netted an estimated $80,000.

With his own election assured, Obama has also continued his travel on behalf of Senate candidates and the Democratic presidential ticket of Sens. John Kerry (Mass.) and John Edwards (N.C.).

In a three-state blitz last Sunday, Obama traveled to North Carolina, South Carolina and Florida to energize the Democratic base.

He attended black church services in Raleigh, N.C., on behalf of Senate candidate Erskine Bowles (D) then traveled to Columbia and Orangeburg, S.C., where he appeared at rallies with state Superintendent of Education Inez Tenenbaum, the Democratic Senate nominee.

Obama finished the day at a rally for Castor and the Democratic presidential ticket in Daytona Beach, Fla.

Through Sept. 30, Obama had raised a little more than $14 million and had almost $1.8 million left in the bank.