Preparing for a leadership race that’s two years off but already heating up, Senate Majority Whip Mitch McConnell (R-Ky.) and Conference Chairman Rick Santorum (R-Pa.) are criss-crossing the country to raise money and stump for candidates running this fall.

McConnell made a campaign swing to aid Colorado Senate candidate Pete Coors (R) on Monday. The same day, Santorum hosted Oklahoma Senate candidate and ex-Rep. Tom Coburn (R) at a $43,000 fundraiser in Philadelphia.

Santorum hosted another small fundraiser Wednesday in Pittsburgh for Sen. Jim Bunning (R-Ky.), and on Friday McConnell plans to wrap up his week by headlining a fundraiser for the North Carolina Republican Party. That should provide indirect benefit to Rep. Richard Burr (R-N.C.), who is running for an open Senate seat.

Aides to McConnell and Santorum are adamant that their increasing political activity has one goal only: helping the GOP net more seats on Nov. 2, thus expanding their currently razor-thin, 51-49 majority.

But with both Senators now openly seeking to succeed Senate Majority Leader Bill Frist (R-Tenn.) when he retires in 2006, McConnell and Santorum have begun what amounts to a shadow campaign.

Dollars raised and contributions made aren’t the sole determining factor in leadership races — but it’s no secret that helping colleagues bring home cash that can benefit their campaigns is a key way to win allies.

Both McConnell and Santorum benefit from sophisticated political operations that are able to raise and contribute large sums of cash to candidates in tough races this cycle.

While the early start to the leadership race could produce some awkward, even divisive moments over the next 18 months, one benefit of the face-off will be the dollars the race will help drive into GOP campaign coffers.

Republican leaders have already made a point of thanking the fund-raising efforts undertaken by Santorum and McConnell.

“Both have been outstanding leaders for our team,” said Sen. George Allen (Va.), chairman of the National Republican Senatorial Committee, carefully avoiding taking sides in the pending battle.

For both Senators, the primary vehicle for campaign assistance is their leadership political action committees: McConnell’s Bluegrass Committee and Santorum’s America’s Foundation. And both have ratcheted up their efforts to raise money directly for candidates and appear at fundraising events for them.

Santorum runs one of the largest Congressional leadership PACs measured by dollars raised, while McConnell controls one of the most efficient in terms of dollars distributed.

As of June 30, the last date for which all leadership PACs reported their filings, America’s Foundation had taken in more than $2 million in receipts during the first 18 months of the 2004 cycle — a total surpassed in the Senate only by Frist and Sen. Trent Lott (R-Miss.).

With less than $750,000 in receipts, the Bluegrass Committee couldn’t even crack the top 20 of House and Senate leadership PACs in dollars raised, according to a Roll Call analysis of reports at the Federal Election Commission.

But McConnell’s PAC had handed out more than $302,000 in donations — nearly $280,000 to House and Senate candidates, and the remainder to state and local candidates. Measured by total donations, McConnell’s PAC was surpassed among Senate Republicans by only Frist.

As of June 30, Santorum had dished out $186,000 in contributions to candidates and to Republican Party committees — a large sum, but almost 40 percent less than McConnell. (America’s Foundation files with the FEC monthly, and, including his donations in July and August, Santorum’s total Congressional contributions were close to $220,000 as of Aug. 31.)

The overwhelming beneficiaries of each Senator’s largess are fellow GOP Senators and candidates in the most highly contested Senate races. The Bluegrass Committee dished out $185,000 to Senate campaigns, plus another $30,000 to the NRSC and $35,000 to the leadership PACs of fellow Senators.

By the end of August, America’s Foundation handed over $150,000 to Senate candidates and another $30,000 to the NRSC. While most contributions to House candidates focused on GOP candidates running in the Keystone State, Santorum did drop $5,000 into a noteworthy House account — that of Rep. Mark Kennedy (R-Minn.), who may vote in future Senatorial leadership races if he wins an expected 2006 challenge to Sen. Mark Dayton (D-Minn.).

McConnell has managed to be so efficient with his PAC by eschewing direct-mail pitches and relying on a core group of supporters in Kentucky as well as the PAC community inside the Beltway.

Out of the nearly $750,000 he raised, just $1,210 came from donations of less than $200, according to FEC reports. By contrast, he raised $387,000 from PACs, almost half of his contribution total.

Santorum, for his part, has followed Lott’s model, operating a massive direct-mail operation that is costly but keeps his name and his favorite issues at the finger-tips of his staunchest supporters. Santorum allies said that donors to the PAC receive eight to 10 mailers a year. By June 30, America’s Foundation had taken in more than $612,000 in small-dollar donations.

Partly because of his aggressive style and partly because he heads up the Senate Republican outreach to K Street, Santorum is one of the most successful fundraisers from PACs in Congress, lobbyists say. By the end of August, America’s Foundation had taken in $949,000 from PACs.

However, leadership PACs for both Santorum and McConnell are just part of their political operations, with each expanding direct fund-raising for key races this year.

In the 2002 election cycle, Santorum began hosting what he calls “Breakfast Clubs”, mostly in Philadelphia. At these gatherings, a group of financial backers would hold quick events for Senators and challengers that cost the candidates nothing but the time it takes to get to the City of Brotherly Love.

So far this cycle, 16 candidates have trekked through Philadelphia — or, in a few cases, Pittsburgh, as was the case with yesterday’s Bunning fund-raiser. Including two events for the NRSC, Santorum’s allies estimate that his Breakfast Clubs have brought in more than $700,000 to GOP candidates and the party committee.

McConnell, too, has taken to hitting up his donors for checks made out directly to candidates most in need. The Bluegrass Committee has begun a “conduit contribution program” modeled on one Frist runs.

At an Aug. 9 event in Kentucky, McConnell’s donors bundled more than $500,000 for the Senate campaigns of Thune, Burr and Rep. Jim DeMint (R-S.C.), according to sources close to McConnell. Each candidate made off with more than $150,000.

Other Senate candidates, including Rep. David Vitter (R-La.), who’s running to succeed retiring Sen. John Breaux (D), are now benefiting from this conduit program, the so-called “Bluegrass Majority Board.”