WASHINGTON — Nominally independent groups are lifting video from candidates' websites, adding a few new images and some fresh narration — and then calling them their own television ads.

Call it a political remix.

High-quality footage is just sitting on their campaign websites, available to anybody — say, friends who run super PACs and outside groups — who might want to make it part of a campaign commercial in this year's high-stakes Senate elections. And outside groups are stepping up and taking advantage.

Campaign laws bar any candidate from coordinating with these groups, which may share the goal of winning an election to Congress this year. But nothing says a group like the Kentucky Opportunity Coalition can't use the public footage of Sen. Mitch McConnell, R-Ky., in a campaign commercial that could help the Senate's minority leader win a sixth term. So the Kentucky Opportunity Coalition has done just that.

"Tell Sen. McConnell to keep fighting for our troops and veterans," a female narrator says over the slow-motion footage of McConnell greeting veterans.

Outside groups are running ads in Alaska and Iowa, with video teed up for use in North Carolina and Minnesota.

Such efforts reflect the fierce competition of this year's elections, in which Republicans need to gain only six seats to win control of the Senate and have a profound influence over the last two years of President Barack Obama's presidency.

The videos represent a political opportunity that has emerged in the four years since the Supreme Court cleared the way for outside groups to raise and spend unlimited amounts of money.

Technically, the campaigns cannot tell the super PACs or other outside groups what to do. But the walls between the campaigns and the independent groups are flimsy at best. And it doesn't take too much effort to figure out how outside groups can use the videos to help their friends.

However brazen, the practice seems to fall within exemptions to Federal Election Commission rules that ban direct collaboration between campaigns and their independent allies.

"With each election cycle, the outside groups are getting increasingly bold, as are the candidates," said Paul Ryan, senior counsel at the Campaign Legal Center.

Ryan's organization, along with fellow watchdog Democracy 21, has objected to the pro-McConnell group using video from the Republican senator's website in a television ad running in Kentucky. The group is expected to run two more ads in the next two weeks. With their radio buys, its expenditures are expected to reach $1.8 million.

"Any materials used came from the public domain and were not coordinated with any candidate or campaign," said Tom Josefiak, an attorney for the Kentucky coalition, which is organized under a section of the tax code that does not require it to disclose its donors. "The FEC has said repeatedly that the use of this kind of footage is not a violation."

A McConnell spokesman declined to comment on the ads.

The scenario repeats itself in competitive races elsewhere. In Alaska, a group called Put Alaska First is running ads backing Sen. Mark Begich, a Democrat. In Iowa, the Environmental Defense Fund pulled footage from Rep. Bruce Braley's site to suggest the Senate hopeful is meeting with workers at a green job site. Braley is also a Democrat.

Others are close behind. Democratic Sen. Kay Hagan and her Republican rival, state House Speaker Thom Tillis, have each uploaded digital files for allies to use. In Minnesota, Democratic Sen. Al Franken has a cluster of ads on his site, helpfully cut into files that clearly advertise what's available: "Franken in diner," "Franken talking to men" and "Franken reading to children."

While watchdog groups say the use of these videos runs counter to election laws, the outside groups point to a 2012 statement from then-FEC chair Caroline Hunter and two other Republican members of her commission. In it, they affirmed a "common-sense approach" to limiting groups repurposing candidates' videos for their own. "What is at issue here is background video," Hunter said in the statement.

That essentially gave permission for outside groups to sprint forward.

Take the latest from McConnell, who is facing a tea party-style challenger in his primary. On his campaign website, a two-minute video includes footage of him working, chatting with his wife, smiling into the camera and posing with voters. It looks remarkably like a flashy campaign ad — and quickly became one, sponsored by the Kentucky Opportunity Coalition.

Begich, who is among the Democrats' most vulnerable incumbents, uploaded a four-minute collection of video clips to be spliced together for 30- or 60-second spots. The montage begins with the first-term senator greeting a fisherman on his boat and then going for a ride off Alaska's coast. The video has no narration and a guitar riff loops in the background. Some of it is in slow motion and all of it puts Begich in a positive light.

In case allies didn't get the hint, the video clip has a link: "Download this video in HD."

Braley, the Iowa Democrat running for Senate, has uploaded about five minutes of footage of him interacting with voters. Veteran Democratic Sen. Tom Harkin is retiring and holding that Senate seat is key to the Democrats' prospects of holding the Senate majority.

"The content we post online is a way for our volunteers and supporters to learn more about Bruce and what he stands for," Braley spokesman Jeff Giertz said.

The Environmental Defense Fund considers itself among the intended audience.

"It's all stock footage or from publicly available sources," said Keith Gaby, a spokesman for the Environmental Defense Fund. "That's common practice when you're on a budget and fighting very well-funded special interests."

In North Carolina, Hagan — she's another Democrat already facing millions of dollars in negative ads — has uploaded a two-minute video of her touring a hospital with doctors, working at her desk and meeting with veterans. In some shots, she leans against a pickup truck parked in the woods. In others, she sits at a diner listening to constituents.

Her likely Republican rival has done the same. In Tillis' three-minute video, the speaker of the North Carolina House tours a business, walks down the street holding his wife's hand and poses for a picture with his dog.