An organization dedicated to electing scientists and STEM professionals is endorsing four more Democratic House challengers Monday.

Monday’s congressional endorsements — part of a broader rollout of state and local candidates – comes in traditionally GOP seats, two of which may look more competitive for Democrats in 2018, while two others still look more challenging to flip.

Endorsees will receive support from the PAC (314 Action Fund) and will be touted to the group’s 225,000 members, including 40,000 contributors. 314 Action has raised about $1 million this year and is hoping to raise between $5 and $7 million for the 2018 cycle to allow it to make independent expenditures.

Since its candidate training recruitment efforts began in January, 314 Action has been in touch with 6,000 scientists and STEM professionals interested in running.

In just one race so far (California’s 39th), the group has had to choose among multiple scientists. It backed pediatrician Mai-Khanh Tran, who is among five Democrats hoping to take on 13-term GOP Rep. Ed Royce. Inside Elections with Nathan L. Gonzales rates the race Lean Republican.