What I found online:
Forward Blue is associated to Switchboard, which is a firm that creates software/data tools to assist with fundraising for political parties.
Scam Detector rates FB at 61.5/100, notably saying “The algorithm detected potential activity related to phishing, spamming, and other factors…” Commenters reported requests for donations with 400% or 500% donation matching. That alone is suspect.
I won’t be donating to them.
Follow
Donate directly to the campaign of the candidate from their official campaign site.
I was so pissed when I discovered that my "use them as you need them" donations got sent to Hail Mary candidates I could have spit.