Washington (CNN) - Even as many pollsters predict sweeping gains for the Republican Party this November, Democratic National Committee Chairman Tim Kaine is striking an optimistic tone, saying the party's achievements over the last two years will resonate with voters.
"Is the climate tough? Sure it is, because too many people are hurting. But we think as the voters start making decisions about who they're going to vote for, they're making a choice. It's a choice between the Democratic Party, which has done heavy lifting to take an economy that was shrinking and get it back to growing," Kaine told CNN's Wolf Blitzer, Anchor of "The Situation Room."
"We can't afford to go back and put the keys back into the hand of the party that ran us into this recession and this lost decade. I think voters will understand," he said.
Kaine will deliver a national address on Wednesday to kick off the 2010 fall mid-term election campaign season at the University of Pennsylvania in Philadelphia.
The speech will "discuss the economic progress that the country has made as a result of the bold actions taken by President Obama and Congressional Democrats," the DNC said in a statement.
Yet, many Democratic candidates facing tough races are distancing themselves from the national party in the final months of the midterm election cycle, weary of their party leaders' unpopularity with voters.
Instead, voters around the country have been seeing ads like one recently released by Rep. Jason Altmire, D-Pennsylvania, which touts his independence from President Obama.
"Too many people in Congress just vote the party line. But Jason Altmire, he's not like that. Jason's independent, no doubt about it. You saw it when he voted against health care. And when Jason opposed the Wall Street bailout. I like that Jason Altmire is not afraid to stand up to the President. And Nancy Pelosi," the ad says.
Kaine said that while he thinks Democrats should "be proud of the heavy lifting they've done," he "wasn't prepared to say" that the DNC would cut off funding to those candidates who have spoken out against their party.
"We've always been a big tent. That's one of the strengths of our party. It can create some challenges at times, but overall we don't want to be the party that throws folks over the side because they run an ad they don't like or cast a vote that we don't like," Kaine said.
But Kaine did concede that he might not be as helpful to candidates who aren't towing the party line.
"You won't be surprised, Wolf, to know that I tend to be a little more helpful to those who are energetically and enthusiastically telling about the good things their party has done," Kaine said.
Democratic Gov. Ed Rendell of Pennsylvania will join Kaine at the event Wednesday.
Pennsylvania, a major 2008 battleground state, has emerged as a key state this election cycle. Several key races, including a gubernatorial race to replace the term-limited Rendell, a contentious Senate race to replace Democratic Sen. Arlen Specter, and several close House races, could significantly alter the make-up of both national parties.
In an online video released by Organizing for America Tuesday, David Plouffe, an outside adviser to President Obama, outlined the challenges the party faces in states like Pennsylvania, and implored supporters to get out the vote in the last days of the campaign season.
OFA is President Obama's political organization that is now run out of the Democratic National Committee.
Plouffe predicted that there will be about 70 house races in play this November, as well as about 15 competitive Senate races, and about 24 tough gubernatorial races. He dismissed predictions of sweeping Republican victories, and hyped the power of OFA's ground teams to create the turnout needed for Democratic victories.
"There's no doubt that we face a lot of political headwinds out there, but with your help we can do a lot better than the pundits and the so-called political experts believe," Plouffe said.
"If enough of you go out and volunteer, you can swing some of these states and districts into the Democratic column," he said.