What a difference a percentage point makes — especially when all you’ve got is 1 or 2 of them.

To qualify for what will be a supersized Democratic debate this month, presidential candidates had to receive at least 2% support in four polls sanctioned by the Democratic National Committee, as well as donations from at least 130,000 unique supporters. Some polled far higher than 2%, while others only just cleared the bar.

When survey results are that low, they are said to be within the “margin of error” of zero, meaning there’s technically a chance the candidate has close to no support at all.

“It’s not materially different than polling at zero,” Patrick Murray, director of polling at Monmouth University, said in an interview.

But in this early stage of the campaign, candidates in that statistical no-go zone still stand a chance at gaining a lifeline by making it into a nationally televised debate.

The next Democratic debate, Oct. 15, will feature 12 candidates, the most of any televised showdown in presidential campaign history. Rep. Tulsi Gabbard of Hawaii and billionaire hedge fund investor Tom Steyer both qualified for the October debate after narrowly missing out on September’s.

Gabbard’s poll numbers in qualifying national and state polls have hovered between 0 and 2% throughout the campaign. Steyer has not risen past 1% in any qualifying national surveys, but he has recently been accruing between 2% and 4% in polls of early-nominating states.

When a candidate’s poll numbers are this low, simply increasing name-recognition can play a significant role in reaching the threshold to make the debate stage.

“You have candidates that got in by basically doing things that strategically got their name recognition up enough that they could meet these very low polling marks,” Murray said.

“In Gabbard’s instance, three of her four qualifying polls have been in Iowa and New Hampshire, where she’s simply spent a lot of money on billboards to get her face and name out there,” he said. “Tom Steyer has quite literally bought himself name recognition in those early states, with online and TV advertising.”

Steyer has been spending millions of dollars over the past two years on TV advertisements calling for President Donald Trump’s impeachment. The move has irritated some members of his own party but has also raised his profile significantly.

And with the House having recently opened an impeachment inquiry against the president, Steyer may take the opportunity to claim vindication on live television, in his first debate appearance.

Other low-polling candidates have had more consistent numbers. Andrew Yang, a businessman who has pledged that as president he would offer a monthly universal basic income of $1,000 to all American adults, has not missed a debate, and his numbers have inched steadily upward: He now averages over 3% in nationwide polls, according to Real Clear Politics, up from roughly 1% a few months ago.

Stephanie Cutter, a Democratic consultant who was President Barack Obama’s deputy campaign manager in 2012, said it was not atypical for an outsider like Yang — who has no background in politics — to command interest from a small but considerable portion of the electorate.

“There’s an appetite for the non-politician,” she said. “It doesn’t mean they make it over the finish line, but people are entertaining it at a marginal level.”

But as the debate season continues, the qualification criteria will only tighten, inevitably narrowing the field. At November’s debate, candidates will need at least 5% support in two polls in early-nominating states or 3% in four early-state or national polls. (So far, just five candidates have hit the threshold, and three more are on the cusp.)

It is not unheard-of for candidates polling in the single digits to eventually seize the nomination. In fall 2003, Sen. John Kerry often polled in the single digits, receiving as low as 4% in one nationwide CBS News poll; in the same survey, Sen. John Edwards garnered only 2%. Kerry went on to become the Democratic nominee, and he chose Edwards as his running mate.

But Paul Maslin, a longtime Democratic pollster who worked on Howard Dean’s presidential campaign in 2004, noted that none of today’s single-digit candidates are polling as strongly in Iowa, New Hampshire and other early voting states as Kerry or Edwards were around the same time in 2003.

“I think the vast majority of primary voters are now realizing there’s only one of two or three possible winners,” Maslin said. “They have said to the vast majority of folks who are 3% or lower, ‘Thanks but no thanks.’ “

As for the upcoming debate, he said, “Most of the Democratic primary voters would probably rather this be the last time you have that many people on the stage.”