CNN Just Changed Its Debate Rules. That's Great News for Carly Fiorina.

Following a strong showing in the first round of debates, Fiorina appears likely to take the main stage in the second one.

Republican presidential candidate Carly Fiorina participates in a presidential pre-debate forum hosted by Fox News and Facebook at the Quicken Loans Arena on Aug. 6 in Cleveland, Ohio. (Chip Somodevilla AFP/Getty)

After weeks of sparring, the great war between Carly Fiorina and CNN has been decided. And Fiorina has emerged the victor.

Late Tuesday, CNN announced it would change its criteria for GOP candidates to qualify for the main stage of its presidential debate in Simi Valley, Calif., on Sept. 16. The old rules, Fiorina's supporters said, unfairly weighted polls taken before the first GOP debate on Aug. 6, and therefore before many Republican voters knew who Fiorina was. As she's climbed in the polls following a strong performance in the first debate, her camp has argued that CNN's methodology is unfairly holding her back.

Up until Tuesday, CNN had said Federal Election Commission law prevents the network from changing its debate criteria. Under the new rules, more weight will be given to polls taken after the first GOP debate, and to polls in early primary states.

Here are the full new rules for qualifying for the main debate stage, referred to here as "Segment B" of the debate:

7. The first 10 candidates—ranked from highest to lowest in polling order from an average of all qualifying polls released between July 16 and September 10 who satisfy the criteria requirements outlined in this document—will be invited to participate in "Segment B" of the September 16, 2015 Republican Presidential Primary Debate. In the event of a tie for 10th place, the tie-breaker will be an average of all qualifying polls released between August 26 and September 10. The second tie-breaker will be an average of all qualifying polling conducted in Iowa, New Hampshire, South Carolina, and Nevada released between July 16 and Sept. 10.

7a. In the event that there is a candidate (or candidates) polling in the top ten in qualifying polls between August 7 and September 10, but not polling in the top 10 in polls between July 16 and September 10, that candidate (or candidates) will be added to the debate stage and will appear in "Segment B" of the debate.

The Republican National Committee—which had come under fire from Fiorina's campaign for setting the original (and according to Team Fiorina, flawed) criteria with CNN—applauded the new rules. "I applaud CNN for recognizing the historic nature of this debate and fully support the network’s decision to amend their criteria," RNC Chairman Reince Priebus said in a statement.

The RNC was surely wary of the optics of keeping its field's sole female candidate off the main stage. Campaigning in Iowa last week, Fiorina made a point of calling out both CNN and the RNC for refusing to change the debate criteria, and hinted that they were purposefully trying to keep her off the stage. Earlier on Tuesday afternoon, before CNN announced its new criteria, Fiorina's campaign published a letter on Medium from supporters asking CNN to include Fiorina in the debate.

It would be an understatement to say Fiorina's campaign is happy with the news. Fiorina had a breakout performance in the first debate, and has been looking to use that performance as a springboard onto the main stage of the next debate. Judging by her recent swing through Iowa, it's something that Republicans in the early primary state want too.

Sarah Isgur Flores, Fiorina's campaign director, tweeted as if Fiorina's place on the main stage is now certain:

However, just because Fiorina has a chance to make it onto the main stage now does not mean she'll necessarily be kicking another candidate off the island. The way the new CNN criteria works, if a candidate polls in either the top ten of the earlier pool (July 16-Sept. 10) or the later one (Aug. 7-Sept. 10) they'll be placed in the top tier at the debate.

CNN's acquiescence to the complaints from Fiorina's supporters could set a risky precedent for future debates. Surely this is not the last time a candidate will feel he or she is being wrongly deprived of air time. With so many Republican candidates running for president, one of them will train their gaze on the next media outlet hosting the next debate. Whether or not the company caves to the next source of pressure will be telling.

Tim Alberta contributed to this article