Joe Biden
Vice President Joe Biden told fellow Democrats Wednesday he was trying to decide whether he could give his "whole heart and [his] whole soul" to a presidential run. Pictured: Biden delivers remarks at the U.S.-Ukraine Business Forum in Washington, July 13, 2015. Reuters/Yuri Gripas

Vice President Joe Biden is running out of time to keep up his "aw, shucks" routine in deciding to announce whether or not he will run for president in 2016. On Monday, CNN released its candidate criteria for the first Democratic presidential debate, which is set for Oct. 13, 2015.

To receive an invite, a candidate must file a statement of candidacy or announce that they will file one by Oct. 14. In addition, a candidate must be polling an average of at least 1 percent by the slew of polling outlets approved by CNN.

Biden already has a base of early support, according to a new poll by the Wall Street Journal and NBC: 17 percent of Democratic primary voters say Biden would be their pick if he ran.

Hillary Clinton dropped from 53 percent to 42 percent when Biden was listed as a potential challenger, while Vermont Sen. Bernie Sanders stayed at 35 percent when Biden was included in the lineup, "compared with 38 percent when [Biden's] not in the mix."

Team Biden has told the press that the vice president is still weighing his options. Meawnhile, 50 top Democratic Party fundraisers, operatives and activists have put out a letter urging Biden to jump in.

For her part, Biden's wife Jill recently signaled her support. "Of course, Dr. Biden would be on board if her husband decides to run for president but they haven't made that decision yet," Jill Biden spokesman James Gleeson recently said in a statement.

Eligibility will be judged by the candidates' standing in ABC News, Bloomberg News, CBS News, CNN, FOX News, Gallup, Marist University, McClatchy News Service, Monmouth University, NBC News, The New York Times, Pew Research Center, Quinnipiac University, Time, USA Today, The Wall Street Journal and The Washington Post.