Support for same-sex marriage in the US Senate is growing, but additional gains will be difficult to achieve

In the last few years, state after state and senator after senator have declared their support for full marriage equality. Such momentum suggests that the goals of same-sex marriage advocates will be realized sooner rather than later. In new research, Sean Theriault and Herschel Thomas analyze when senators announce their support for same-sex marriage. Contrary to the popularly held belief that their decisions will quickly snowball into filibuster-proof numbers, they find that most of the easy successes have already been achieved.