In part, the short video has the feel of a campaign ad: The strains of soft music, the iconic snapshots of rugged Arizona desert, the candidate earnestly engaged with her constituents.

Interspersed with the slick montage of photos and sound, though, is a video close-up of Rep. Gabrielle Giffords gazing directly at the camera, offering not a campaign promise but a goodbye, a thank-you message to her supporters in a voice that is both firm and halting.

“I have more work to do on my recovery,” the congresswoman says at the end of the two-minute-long “A Message from Gabby,” appearing to strain with all of her will to communicate. “So to do what’s best for Arizona, I will step down this week.”

Arizonans had to know in their hearts that this day was coming.

A bullet to the brain, from point-blank range, is a nearly impossible obstacle to overcome, even for a congresswoman known for pluckiness and fight. Giffords seemed to accept that reality in the video announcing her resignation from Congress, which also included a promise to return one day to her mission to help Arizonans.

The clip, posted to YouTube and on her Facebook page, pastes together 13 sentences into a fluid announcement. Giffords wears a bright red jacket eerily similar to the one she was wearing a year ago when she was nearly assassinated. She looks straight into the camera, almost begging the viewer to listen.

But the video also includes images of the 41-year-old struggling at rehab and walking along a leafy street with husband Mark Kelly with an obvious limp. And Giffords acknowledges that, at least for now, she isn’t up to taking on a re-election challenge.

The announcement sets off not one but two elections cycles to replace her. The first will be a special primary election that Gov. Jan Brewer must call sometime in April, with a general election in June to fill out the remainder of Giffords’ term.

The second cycle will concern the regular full two-year term, with the primary scheduled for August and the general election in November.

In between, the 8th Congressional District that Giffords currently represents will change under redistricting. It will become the 2nd Congressional District.

“We’ve got someone that’s going to move in, hold that seat for the remainder of her (term,) and then we’ll have people out there — probably at the same time — running for that seat … with different lines,” Gov. Jan Brewer said Sunday. “So it will confuse some people.”

Brewer said she spoke with Kelly before the announcement and understood the decision.

“…As her husband said, they have sat, and they have discussed this, and that it would be the best thing for her and for her recovery,” Brewer said. “And I indicated on the telephone with him that knowing Gabby and what she has accomplished in this last year in her recovery, who knows what’s going to happen in the next two years.”

The announcement came just over a year after a gunman opened fire at Jan. 8, 2011, meeting with constituents in front of a Tucson grocery store. Six people were killed, and Giffords and 12 others wounded.

She’s clearly not yet ready for another run for Congress. But she said in Sunday’s video that she’s not done yet.

“I’m getting better. Every day my spirit is high. I will return, and we will work together for Arizona and this great country,” she said.

Bob Christie, Associated Press