DES MOINES, Iowa (CNN) -- While the front-runners slugged it out in the days before Thursday's Iowa caucuses, second-tier Democratic presidential candidates spent the final hours before the big event plugging away in hope of staging an upset.
New Mexico Gov. Bill Richardson, Sen. Joe Biden of Delaware, Sen. Chris Dodd of Connecticut and Rep. Dennis Kucinich of Ohio are all in single digits in a CNN-Opinion Research Corp. poll released Tuesday, while former Sen. Mike Gravel of Alaska rated less than 0.5 of 1 percent support.
Despite the long odds, however, many of the single-digit candidates braved Iowa's single-digit temperatures Tuesday to deliver their closing pitches at house parties, gyms and diners before the first contest of the 2008 presidential race.
"Some say I've thought more about how to be president than to get elected president," Biden told CNN. "I'm trying to rectify that."
Dodd used an event in the northeastern town of Oelwein to tout his leadership in stalling a bill that would grant legal immunity to telecommunications companies who cooperated with the Bush administration's warrantless surveillance program, pointing out that neither Biden nor front-runners Sens. Hillary Clinton and Barack Obama would return to Washington to support his efforts.
"If you want to lead in 2009, how about showing some leadership in 2007?" Dodd asked. Though his effort to filibuster the bill failed December 17, Senate Majority Leader Harry Reid decided by day's end to put off the vote until after Congress' holiday recess.
Dodd told supporters that he admired "people who want to fight ... but at the end of the day, people want to know if you can produce some results at the end of those fights."
Most Republicans skipped campaigning on Tuesday, leaving Iowa to the candidates at the top of the most recent polls -- former Arkansas Gov. Mike Huckabee and former Massachusetts Gov. Mitt Romney. Sen. John McCain of Arizona spent the day in New Hampshire, which holds its primary in a week.
McCain was ranked fourth in Tuesday's CNN poll in Iowa, but a new poll released Wednesday put McCain and Romney in a tie for first place in New Hampshire, with each grabbing the support of 29 percent of likely Republican primary voters.
McCain won the New Hampshire primary in 2000.
Republican results will be tabulated by a straightforward ballot process Thursday night. But the second-tier Democrats face a tougher process than their GOP counterparts: Anyone who fails to win the support of at least 15 percent of caucus-goers on the first try is deemed "non-viable," freeing their supporters to select other candidates.
Final results are calculated through a formula based on voter turnout in the past two general elections.
Richardson, the highest-ranking among the single-digit Democrats, drew 7 percent -- compared with 33 percent for the top-rated Clinton, 30 percent for Obama of Illinois and 22 percent for former North Carolina Sen. John Edwards, the party's 2004 vice presidential nominee.
In campaign events Tuesday, Richardson touted his experience as a top diplomat in the Clinton administration in dealing with hostile states such as North Korea, Iran and Cuba -- but said that as governor of a Western state, "I don't have the charisma or the projection that these candidates that are based in Washington in the Senate have." Watch Richardson predict an upset in Iowa »
"I've asked the voters to look at the candidates not on who has the most money or the most charisma or who has the best political pedigree, but who can change this country and give it hope," Richardson told CNN. "You need experience, you need a record and that is why I'm running."
And Biden reminded supporters in Indianola, south of Des Moines, that he was warning about the risks posed by Pakistan -- "the most dangerous nation in the world" -- well before the crisis sparked by last week's assassination of that country's former premier, Benazir Bhutto.
"Imagine the consequences of the failure of this president or the next president being able to deal with and stabilize that nation," said Biden, the chairman of the Senate Foreign Relations Committee. "Imagine the consequences of a radicalized Pakistan, with the jihadis in control -- and in control of all of those nuclear weapons."
Pakistan tested nuclear weapons in 1998 and is currently estimated to have an arsenal of about 55 devices. E-mail to a friend