Kevin Huang/Fight For the Future

The Federal Communications Commission has extended today's deadline for filing comments on its controversial Net neutrality proposal due to a last-minute wave of traffic that's crashing its site for some.

"The deadline for filing submissions as part of the first round of public comments in the FCC's Open Internet proceeding arrived today," said FCC spokeswoman Kim Hart. "Not surprisingly, we have seen an overwhelming surge in traffic on our website that is making it difficult for many people to file comments through our Electronic Comment Filing System."

"Please be assured that the commission is aware of these issues and is committed to making sure that everyone trying to submit comments will have their views entered into the record," Hart said, adding that the new deadline for submitting comments is midnight Friday.

The proposal, spearheaded by FCC Chairman Tom Wheeler, would reinstate regulations over how Internet traffic is treated by Internet service providers. The FCC's prior open Internet rules were tossed out by a federal appeals court in January. This latest effort has ignited a firestorm of protest among consumer advocates who feel it caters to big broadband companies by allowing so-called fast lanes for priority traffic on the Internet.

The FCC's online comment system has been vulnerable in the past -- and, if nothing else, is old. Last month the site stumbled under heavy traffic after comedian John Oliver capped a 13-minute segment about Net neutrality. Chairman Wheeler appealed to Congress in March to increase the agency's funding so that it could pay for more staff and upgrades to its outdated information technology systems.

"We have more than 200 relic IT systems that are costing the agency more to service than they would to replace over the long term," Chairman Wheeler said in his testimony to the US House of Representatives Committee on Appropriations. "We must overhaul, upgrade, secure and replace IT systems that are antiquated relics - costly to maintain and harmful to agency productivity."

Recognizing its technological limits, the FCC is also offering another option for those who don't want to mess with the official online submission process. Hart said the public can also send an email to openinternet@fcc.gov and it will be entered into the public record.

As of last night, the FCC had received more than 677,000 comments on the proposal. Today, the agency said that number has topped more than 780,000 comments.

While a tremendous response to an important issue, it is not the largest number of comments the FCC has received. A little over a decade ago, the FCC received more than 1 million comments after pop star Janet Jackson's 2004 "wardrobe malfunction" during the Super Bowl half-time show exposed her breast on live television. A media ownership proceeding in 2003 generated more than 2 million comments. Of course, in these two examples most of the comments were submitted via traditional mail.

CNET senior writer Marguerite Reardon contributed to this story.