Seattle did once have an NHL franchise (in fact, it was a Stanley Cup-level squad), but unfortunately the Metropolitans never found success after the 1918 influenza epidemic. Since then the city has supported a junior league team known as the Seattle Thunderbirds.
Although the Thunderbirds are popular in Seattle, they are not as popular as other Western Hockey League teams. Their arena is small, and while KeyArena is still available, it is not suitable for hockey.
For Seattle to have an NHL team, it would need to either modify KeyArena, expand the home ice that the Thunderbirds use, or just build a new stadium.
I'm pretty sure Seattle fans would love the opportunity to have a hockey team ,especially after the loss of the SuperSonics basketball team. The novelty of an NHL team would certainly distract them from the futility of their other two Big 4 teams.
Potential names for a Seattle franchise include:
Mets: an abbreviation of Metropolitans, although I'm pretty sure that baseball team in New York trademarked that name.
Thunderbirds: Like the Seattle Sounders, formerly of the USL and now of Major League Soccer, the team could just borrow the name of its junior team.
Warriors: It just fits them perfectly.