Republican and Democratic candidates spent the waning hours of Campaign 2006 hammering away at a message now familiar to millions of voters poised to go to the polls Tuesday: We can do a better job than them.

"The Democrat philosophy is this: If it breathes, tax it, and if it stops breathing, find its children and tax them," President Bush shouted to Republicans rallying in Pensacola, Fla.

"They can't run anything right," countered former President Clinton, campaigning in Virginia for Democratic Senate candidate Jim Webb.

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The day also brought a reminder of Bush's fragile standing in the polls when Florida Republican gubernatorial candidate Charlie Crist skipped the presidential rally to make a speech of his own hundreds of miles away.

Bush ignored the flap.

"I strongly suggest you vote for Charlie Crist to be governor of the state of Florida," he said.

Karl Rove, the president's top political strategist, didn't hide his disappointment in Crist's decision.

"Let's see how many people show up in Palm Beach on 24 hours notice [for Crist], versus 8,000 or 9,000 people" expected for the president's speech, Rove said.

Some late polls suggested momentum was swinging the Republicans' way, and Ken Mehlman, the party chairman, told allies the surveys summoned memories of 1998, when the GOP lost seats but held power.

Democrats steadfastly refused to say so in public, but some Republicans signaled privately they expected to lose more than 15 seats, and control of the House with them.

Among GOP-held open seats, those in Arizona, Colorado, New York, Ohio and Iowa seemed likeliest to fall. Republican Reps. John Hostettler, Chris Chocola and Mike Sodrel of Indiana; Charles Taylor of North Carolina; Curt Weldon, Don Sherwood and Melissa Hart of Pennsylvania; and Charles Bass of New Hampshire were in particularly difficult re-election struggles.

Democrats also boasted of several election targets in New York, where Sen. Hillary Rodham Clinton and Eliot Spitzer, the Democratic candidate for governor, were expected to win handily.

Easily two dozen more Republican seats were in jeopardy, including one in Texas that may not be settled until next month. There, Republican Rep. Henry Bonilla and former Rep. Ciro Rodriguez, a Democrat, were the leading contenders in an eight-candidate field. A run-off between the two top vote-getters would follow if no one won a majority on Tuesday.

In contrast, only a few Democratic incumbents appeared in jeopardy, including Reps. John Barrow in Georgia; Melissa Bean in Illinois and — in a race that bore no impact on the broader party struggle — William Jefferson in Louisiana. Jefferson, ensnared in a federal corruption investigation, faced a likely runoff on Dec. 9, possibly against fellow Democrat Karen Carter.

After months of pursuing the Republicans, Democrats declined to say they would catch them.

"From the Iraq war to the economy to how the Congress does its work, the American people want a different direction — and that's what Democrats offer," Rep. Rahm Emanuel of Illinois, the head of the House Democrats' campaign committee, said Monday.

"We have never said we're going to take control of the Senate. We have said we're on the edge. That's where we are," said Sen. Chuck Schumer, D-N.Y., chairman of the Senate Democrats' organization.

Democrats needed to gain six seats to win control of the Senate. GOP Sens. Mike DeWine in Ohio and Rick Santorum in Pennsylvania appeared in deepest trouble, Sens. Lincoln Chafee in Rhode Island and Conrad Burns in Montana somewhat less so.

Rep. Nancy Pelosi of California, in line to become the first woman speaker in history if Democrats win, was in Washington after a weekend of campaigning for candidates in Pennsylvania and Connecticut.

Neither Bush nor Clinton, the president and ex-president, was on Tuesday's ballot, but both campaigned energetically toward the finish line.

"The Democrats want to raise taxes when you're born, when you're working, when you retire and when you die," Bush said in Florida as his audience laughed appreciatively. "In other words, the Democrats' philosophy is this: 'If it breathes, tax it. And if it stops breathing, find their children, tax it."

Campaigning in Missouri, Democratic senatorial candidate Claire McCaskill said it wasn't so. She was in a supermarket meeting voters when one shopper asked her whether she wanted to raise taxes.

"There's nothing to that allegation," she replied. "We're going to cut taxes for the middle class."

She added that previous tax cuts "that just help the very wealthy should be retargeted to the middle class."

As he has repeatedly, the president attacked Democrats for their position on the war in Iraq.

"Oh, they've got some ideas. Some of them say, 'get out right now.' Some of them say, 'get out at a fixed date,' even though the job hasn't been done. One of them said, 'let's move our troops to an island some 5,000 away."'

Former President Clinton provided the rebuttal to that charge from a stage in Rochester, N.Y..

"On this 'stay the course in Iraq' deal, they say we're the cut-and-run crowd," he said. "These people don't look like cut and run to me," he said, gesturing at Eric Massa, a House candidate and Navy veteran, and former Sen. Max Cleland, a triple amputee from war wounds suffered in Vietnam a generation ago.

Republican leaders say that the president's get-out-the-vote push in GOP strongholds was helping. The free media coverage that accompanies a presidential visit was keeping his party from having to spend precious dollars in those districts. And some new polls showed a lift in Republican enthusiasm for voting.

"The president's travels are part of the difference," White House Press Secretary Tony Snow said.

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