I wouldn't consider voting for any of these people in the general election, but I recognize that people often live in gerrymandered districts, and therefore vote in Republican primaries in order to have some influence over their local representatives. For people living in such a district, choosing a least-bad candidate is a way try and moderate the Republican party just a bit.
Candidates are listed by poll-based estimates of their support, which makes it rather clear that Republicans as a whole have sought to reject any kind of meaningful path to zero greenhouse gas emissions.
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Trump: His actions as president may have caused irreversible damage to the global climate.
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DeSantis: He has supported efforts to adapt to the effects of climate change, but not to prevent it.
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Scott: He acknowledges climate change but rejects most efforts to stop it.
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Ramaswamy: He opposes all government efforts to reduce carbon emissions.
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Haley: She supports carbon-capture technology but has denounced efforts to reduce emissions.)
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Pence: He claims climate change is exaggerated and would prioritize domestic energy production.
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Christie: He supports action on climate change with some caveats.
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Hutchinson: He denounces government mandates but supports private renewable energy development.
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Burgum: He has supported carbon-capture as governor, but what he would do as president is unclear.
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Hurd: He acknowledges that climate change is a major threat, but what he would do is unclear.
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Suarez: He has pursued significant emission reductions in Miami.
I think focusing on climate change directly is not the right approach with Republicans. To them it's a culture war discussion, so they'll always point to the most extreme view to strawman their arguments.
I think it's far more interesting to discuss practical solutions that would help improve GPD generally, such as:
These target the biggest sources of pollution, transportation, energy, and industry, but without directly changing regulations or restricting anyone's freedom, it just makes some choices more expensive.