JOHNS CREEK, Ga -- Republican Bob Gray, one of 18 candidates running in the 6th congressional district special election next month, has released a web ad defending President Donald Trump and attacking a Democratic opponent.

Gray, who has consistently polled third in the race, defended Trump's record in the ad and attacked frontrunner Jon Ossoff.

Gray "is committed to being a willing partner for President Trump in Congress," said campaign manager Tyler Jacobs. "That means calling out the Democrats’ flawed, out-of-touch rhetoric whenever necessary."

Ossoff has been followed by Republican Karen Handel in two polls that have been released in the special election to replace Tom Price, now President Trump's secretary for Health and Human Services.

Race to replace Price: New poll shows Ossoff, Handel and Gray leading

The special election is set for April 18. All of the candidates will appear on one ballot, and a runoff is virtually assured in the race. The only way to avoid a runoff would be if one candidate receives 50 percent-plus-one on April 18, almost an impossibility in such a crowded race.

RELATED: Democrats debate Sunday in 6th district race

11Alive has continuing extensive coverage of the special election, which continues to attract national attention, endorsements and donors. You can read our continuing coverage on our politics page.

The district includes portions of Atlanta, Brookhaven, Chamblee, Dunwoody, Doraville, Tucker, Sandy Springs, Roswell, Alpharetta, Johns Creek Milton and Mountain Park. Before it was last redrawn as part of Census reapportionment, Republicans Newt Gingrich and Johnny Isakson held the seat.