"firmly supportive" is correct and usable in written English.
You can use it to describe someone or something that has strong support for someone or something else. For example: "The principal has been firmly supportive of the teachers' efforts to improve the school curriculum."
The newspaper owners of that era, who included one still with us, Rupert Murdoch, were firmly supportive of membership and their editors pulled out all the stops prior to the vote.
But it is firmly supportive of the scheme overall, as are most people who cycle in the area, and many more who have told researchers they'd like to but don't feel safe mixing it with traffic.
The paper, under the political guidance of David Seymour, has remained firmly supportive of Labour's domestic policies and its European enthusiasms, but it has maintained an intractable hostility over both the prosecution of the Iraqi war and the continuing conflict.
Representative John B. Larson of Connecticut, a member of the House Democratic leadership, sent a letter to Ms. Sebelius that read: "Having worked to pass the Affordable Care Act and being firmly supportive of its implementation, I believe that further flexibility needs to be granted to religiously affiliated organizations in this instance".
Chote's life as economics editor of the Financial Times during the first two years of New Labour was made difficult by the Brown camp, but Chote has asked me to point out that the Fleet Street legend about his departure from that post is wrong: the FT was firmly supportive of him, and he eventually left of his own accord.
It is welcome for those candidates firmly opposed to or supportive of same-sex marriage, political experts said Friday, but has created an unwanted and thorny issue for those who have tried to walk a careful line somewhere in between.
Targeting institutional policies – particularly masculinist social institutions such as military, the police force and sport – can more firmly establish an environment that is supportive of gender equality (Barker et al. 2010b).
SBIRT education can establish an evidence-based standard of nursing practice to improve healthcare outcomes, but it must be reinforced with ongoing ED review and supportive educational sessions until practice is firmly established.
So plan a wedding based in reality, and who you are and what kind of wife you want to be: supportive, smart and with two feet firmly in reality.
Now that the matter is resolved, Lake Street Dive feels firmly entrenched at Signature Sounds and appreciates working with supportive folks who, Price said, "don't get in the way".
"The economy's recovery is not firmly established, and we think monetary policy needs to be supportive," Mr. Bernanke said in semiannual testimony to the House Financial Services Committee.
