Rep. Mazie Hirono (D-Hawaii) has a 19-point lead over former Hawaii Gov. Linda Lingle (R), according to a new poll commissioned by the Democratic Senatorial Campaign Committee (DSCC).

The poll had Hirono at 52 percent to 33 for Lingle.

Partisan polls should always be treated as such, and polling in this race has been all over the map in the hard-to-survey state. A recent internal poll from Lingle showed her leading Hirono by 5 points, while a poll conducted for Hirono last month had her up 12.

Before Hirono can face Lingle, she has to win a primary over former Rep. Ed Case (D-Hawaii). The DSCC, which is backing Hirono, said it did not poll the primary. Most expect Hirono to win that race.

The Hill rates the race "lean Democratic."

Hirono released an ad late Wednesday touting her work on education.

The poll of 800 likely voters was conducted by the Mellman Group from July 18-22 and has a margin of error of plus or minus 3.8 percentage points.

This post was updated at 9:40 a.m.