I'm not sure what GOP is so can't be 100% sure. Growing its spine again tends to mean that it used to 'stand up' (defend) for itself (have a spine/backbone), however it lost this ability for a period, and now starting to defend itself again. Sorry not a clear description but hope you understand the meaning.
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Razer"Signs of GOP growing its spine again"
RazerHow can all sentence be a noun phrase, friend ?I'm not sure what you mean here.