With a number of Senate races coming down the wire, and theshowing likely voters breaking toward Republicans, GOP officials are expressing optimism about Nov. 2.
"A year and a half ago, if you had told me we would be in very close races in Washington state and California and Colorado and Illinois and Pennsylvania, I would have been exceptionally happy," Rob Jesmer, executive director of the National Republican Senatorial Committee, said in an interview with Politico.
One of the hardest-fought races in this final week is in Pennsylvania, where Republican Senate candidate Pat Toomey leads Democratic Rep. Joe Sestak by a small margin. A new Time Magazine/CNN/Opinion Research survey out today shows Toomey leading 49 percent to 45 percent, while today's Muhlenberg College/Morning Call poll gives Toomey an 8-point lead -- three points higher than yesterday.
The National Republican Senatorial Committee released its own ad in Pennsylvania today, entitled "Status Quo Joe," in which a narrator says, "Big Wall Street bailouts, higher taxes, more debt, failed stimulus. Sestak voted for it all."
Sestak's liberal grassroots supporters from the Progressive Change Campaign Committee continue to campaign as well, with the aim of making 30,000 phone calls on behalf of Sestak by Friday.
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The polls are also close in the Colorado Senate race -- one of the most expensive contests this year.
Outside groups have so far spent close to $30 million to campaign for either Democratic Sen. Michael Bennet or Republican Ken Buck. Bennet has raised more than $11 million while Buck had raised close to $4 million at last count.
The Time/CNN poll released yesterday showed Buck ahead by one point, 47 percent to 46 percent. A Colorado Pols/RBI Poll showed Bennet ahead by one point, 43 percent to 42 percent, while a Rasmussen survey puts Buck ahead 48 percent to 44 percent.
"I just can't vote for Ken Buck," a Coloradan says in the ad. "He's just too out there," another adds.
One development came after the debate, when Giannoulias admitted his campaign and the Democratic party were behind a mailer sent to conservatives touting a Libertarian candidate as an alternative to Kirk, the Chicago Sun Times reported.
Mr. Obama is traveling to Illinois this weekend to campaign for Giannoulias, and the Democrat is out with a new ad that features endorsements from both the president and first lady. It is the only ad this year to feature Mrs. Obama.
"Alexi is in it for the right reasons," Mrs. Obama says in the positive ad. "He will be a phenomenal U.S. senator."
The latest Rasmussen poll shows Kirk leading by four points, 46 percent to 42 percent.
In California, Democratic Sen. Barbara Boxer is maintaining a single-digit lead over Republican Carly Fiorina in the Time/CNN poll, which shows the race at 50 percent for Boxer and 45 percent for Fiorina.
The Time/CNN poll also had positive figures for California's Democratic gubernatorial candidate, Jerry Brown. He leads his Republican opponent Meg Whitman in the poll 51 percent to 44 percent.
A labor-backed independent group called Working Californians is helping Brown add some star power to his campaign with a new radio spot featuring an endorsement from singer Stevie Wonder. Last week, the group released a radio ad in support of Brown featuring basketball legend Magic Johnson.
Stephanie Condon is a political reporter for CBSNews.com. You can read more of her posts here. Follow Hotsheet on Facebook and Twitter.