National Reciprocity Bill in Senate: What are the Prospects?
A similar national reciprocity bill was put forward by Senator Cornyn in 2013. It came within 3 votes of overcoming the Senate fillibuster. 57 senators voted for it, 43 against it. After the 2016 election, that number should have switched to 58, assuming that all Republicans vote for the bill, and all Democrats who voter for it before will still vote for it.
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33 senators voted against it, and are still in office. The turnover of 10 senators who voted against the bill from 2013 to2017, only switches one vote with clarity. Of the 33 who are still in office, five are up for election in 2018, in states that Trump won. Those five senators are from states with large numbers of concealed carry permits.
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Will they be able to switch two votes to overcome the 60 vote filibuster barrier? It looks to be eminently plausible.
The only reason to vote against the bill is purely ideological. Why would Senator Bill Nelson of Florida want to prevent 1.4 million voters in his state from being able to carry in other states? Permit holders from other states can already carry in Florida. The same is true in Ohio, Missouri, and Wisconsin. Pennsylvania honors permits from 25 other states.