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With nine days to go until the midterm election and the polls tightening in several key races, top Democratic Party leaders claimed Sunday that momentum is on their side and that the so-called "enthusiasm gap" is closing.

Democrats said voters are beginning to wake up to the alleged damage Republicans would do to the country by wielding the controls of Congress -- a warning President Obama has sounded at campaign rallies across the country on behalf of Democratic candidates.

"From this point forward, it's all about turnout and ground game, and we're seeing good early voting trends," Democratic National Committee Chairman Tim Kaine said Sunday on ABC's "This Week," predicting his party would hold the House. "The polling is moving. We really haven't seen since Labor Day polls moving against us. Almost all the polls have been moving for us. Now, we still have some work to do, but what Democrats tend to specialize in is the ground game, the turnout."

The polling offers a more nuanced picture, and Republicans are expressing just as much confidence. In Washington state, Republican Dino Rossi has whittled away Democratic Sen. Patty Murray's lead in recent polls. In California, Democratic Sen. Barbara Boxer watched her lead over Carly Fiorina shrink to 2 points in the latest survey out of Rasmussen.

But Republicans have likewise watched their leads diminish in Senate races critical to their strategy for a congressional takeover. The shifting numbers underscore the unpredictability of a campaign season marked by the rise of outsider candidates, a groundswell in citizen activism and challenges to the establishment on both sides of the political aisle.

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In Pennsylvania, Republican Pat Toomey has traded the lead in recent polls with Democratic Rep. Joe Sestak, despite holding a strong advantage for weeks over his opponent. In Wisconsin, Republican businessman Ron Johnson's lead fell to the 2 points in his race against Democratic Sen. Russ Feingold, according to a St. Norbert College/Wisconsin Public Radio poll released last week. Polls show the Colorado Senate race between Democratic incumbent Michael Bennet and Tea Party-supported Ken Buck a dead heat. And polling in the West Virginia Senate race between Democratic Gov. Joe Manchin and Republican opponent John Raese has been all over the map.

"It's a very competitive race," said Manchin, who has spent the campaign battling charges that he is too close to President Obama and Washington Democrats. He suggested on "Fox News Sunday" that voters are starting to trend toward him.

"Now this last week, people are starting to look at who's performed in West Virginia," he said.

Rep. Chris Van Hollen, D-Md., chairman of the Democratic Congressional Campaign Committee, said on CBS' "Face the Nation" that he's confident Democrats will retain a majority in Congress.

"These big interests are fighting hard to get back in power and I think the American people are waking up to that fact and that's why I think you're seeing a closing of the political energy gap," he said.

But while Obama and his top surrogates are touring the nations in support of Democrats, Republicans are driving up enthusiasm with rallies and cross-country tours of their own. They say the scattered races where Democrats are gaining steam are nothing to worry about and that a nationwide sentiment that resents the expansion of the federal government is on their side.

"There is a vibration out here that is unlike anything I've ever seen before," Republican National Committee Chairman Michael Steele said on NBC's "Meet the Press." "I think you're going to see a wave, an unprecedented wave on Election Day."

Republicans need 39 seats to win a majority in the House of Representatives and 10 seats to win a majority in the U.S. Senate. Steele predicted Republicans would achieve both, though he described the Senate as a tougher climb.

Toomey, in an interview with "Fox News Sunday," dismissed the tightening polls in his Pennsylvania Senate race. Toomey rocked the political scene in the Keystone State when his popularity in the Republican primary forced Sen. Arlen Specter to switch parties in order to run as a Democrat. Specter later lost to Sestak.

Despite the sudden hiccup in Toomey's lead, the GOP nominee said he's confident he'll give Republicans a boost in their quest for 51 seats in the Senate.

"I never expected this to be anything but a close and competitive race," Toomey said. "It's close now, but I feel great about where we are. ... I think the energy and the momentum's on our side."

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