Senate Majority Leader Bill Frist (search) outpaced other potential 2008 presidential candidates in the first half of the year, with his political action committee raising $1.9 million.

That was more than enough for early trips to New Hampshire and contributions to GOP Senate incumbents.

On the Democratic side, Indiana Sen. Evan Bayh's (search) political action committee raised nearly $1.2 million and spent $467,445 in the first half of the year, according to an analysis by the nonpartisan Political Money Line campaign finance tracking service. Bayh's PAC had $1.1 million cash on hand at the end of the period.

Political Money Line focused on the Federal Election Commission reports of possible presidential candidates. Political action committees provide Republicans and Democrats with the money for travel, speeches and donations to other candidates. They are one step from the official presidential campaign committees that signal a White House bid.

While collecting close to $2 million, Frist's political action committee spent $1.7 million in the first six months of the year, leaving it with around $1 million. The Tennessee Republican's PAC contributed to the campaigns of several Republican senators facing re-election in 2006, including Pennsylvania's Rick Santorum (search) and Missouri's Jim Talent (search).

Among other Republicans:

—Nebraska Sen. Chuck Hagel's (search) PAC raised $389,519, spent $273,938 and had $164,665 cash on hand.

—Former New York City Mayor Rudy Giuliani's (search) PAC raised $292,857 and spent $120,428, leaving it with $366,980.

—Virginia Sen. George Allen's (search) PAC raised $197,741 and spent $190,140. It had $218,144 cash on hand.

Among the Democrats:

—Illinois Sen. Barack Obama's (search) PAC raised $851,674, spent $406,564 with $445,110 cash on hand.

—Sen. Hillary Rodham Clinton's (search) political action committee raised $715,851, spent $653,939 and had $145,065 cash on hand. Separately, the New York senator raised more than $6 million between April and June for her 2006 re-election bid and had $12.6 million cash on hand.

—The PAC of former Sen. John Edwards (search) of North Carolina raised $624,813, spent $565,724 with $59,455 cash on hand.