ST. LOUIS — Vice President Joseph R. Biden Jr. admonished Democrats on Friday to shake away their pessimism about the fall elections, arguing that the prospect of historic losses would be minimized because the Republican Party has been overtaken by extreme candidates and stale ideas.
“The reports of the death of the Democratic Party have been greatly exaggerated,” Mr. Biden said, paraphrasing Mark Twain as he addressed party leaders here. “The day after the election, there will be a Democratic majority in the House and a Democratic majority in the Senate. If it weren’t illegal, I’d make book on it.”
As the Democratic National Committee gathered for its summer meeting at Union Station in St. Louis, anxiety marked a stark change for a party that had reveled in back-to-back election cycles that produced control of Congress and the White House. Democrats acknowledged the difficult political climate, but they said that their candidates could benefit from Republican shortcomings.
“The choice is not between Democrats and the Almighty. It’s between Democrats and the Republican Tea Party,” Mr. Biden said, suggesting that most American voters would not tune into the election until after Labor Day. “Voters are going to look at what the Republican Party is really offering — more of the past, but on steroids.”
With 75 days remaining in a midterm campaign that will determine whether Republicans will win control of Congress, the White House dispatched the vice president here to boost the spirits of Democrats who are bracing for the prospect of deep losses in House, Senate and governors’ races. Republicans must pick up 39 seats in the House and 10 in the Senate to gain a majority.
Democrats conceded they are not only fighting against tides of history — only twice in the last 75 years has the president’s party not lost seats in a midterm election — but a bleak economy and an unemployment rate that remains close to 10 percent. To win over voters, Democrats are searching for a balance between trumpeting their legislative achievements and reminding voters they inherited the economic problems.
“We can get in the bunker. We can say, it’s not our fault, it’s the economy,” said Senator Claire McCaskill, Democrat of Missouri. “Or we can remember what it felt like two years ago when we were on the verge of something special in this country. We need to remember that sense of purpose.”
Tim Kaine, the Democratic national chairman, announced that the party raised $11.5 million in July, the second-highest monthly figure of the election cycle. The party had $10.8 million in the bank, he said, which would be used to create an aggressive get-out-the-vote operation aimed at core Democrats and first-time voters who supported President Obama two years ago.
He said Democrats held important structural advantages over Republicans, particularly the strength of their political organization in states across the country.
“There’s a lot of gloom and doom, but I think we’re going to do a lot better than people think,” said Mr. Kaine, delivering a raw partisan speech to a ballroom filled with Democrats, many of whom leapt to their feet as he dismissed Republicans as “easy streeters and country clubbers.”
The Republican National Committee, which has struggled to raise money this year, was still tabulating its July fund-raising figures. Two weeks ago, when members of the Republican committee gathered for their summer meeting in Kansas City, Mo., party leaders conceded that they were worried about the fund-raising disparity with Democrats.
But Republicans believe the political environment will overcome any campaign shortcomings.
Not long after the vice president delivered his speech on Friday, the Republican National Committee issued a statement criticizing him and other Democrats for being out of touch, particularly given the number of people seeking unemployment benefits reached the half-million mark for the first time this year.
“Joe Biden is still desperately trying to convince Democrats that the economy is on the right track,” said Bill Riggs, a Republican spokesman. “It’s clear that Barack Obama and Joe Biden are completely out of touch.”
In addition to the vice president, the administration also sent Kathleen Sebelius, the secretary of health and human services, to address the Democratic gathering. She said the landmark health care law, which will be implemented in phases, is among the reasons voters elected Democrats and should be a central part of the party’s argument.
“We passed a transformational health care bill in spite of daunting odds,” said Ms. Sebelius, a former Democratic governor of Kansas. “The more people understand this bill, the more they’re going to like it.”
A poll released Friday by CNN showed that 56 percent of Americans oppose the health care bill, while 40 percent support it. The sentiment has barely changed over the last five months.
The Democratic National Committee also voted to approve the 2012 presidential primary nominating calendar, setting the date of the Iowa caucuses for Feb. 6, 2012, and the New Hampshire primary on Feb. 14. The contests in Nevada and South Carolina will follow over the next two weeks, with other states beginning their voting after March 6.