By any measure, President Obama has begun his second term with an ambitious agenda: comprehensive immigration reform, a new assault weapons ban, universal background checks, and even possible measures on climate change and voting rights. In all likelihood, he’ll discuss each of these in tonight’s State of the Union. But — insofar that he wants to make progress — he might be better served by staying quiet. Today’s poll from the Washington Post and Capital Insight shows something interesting: When Obama lends his name to proposals on immigration, climate change or the war in Afghanistan, support drops.

Without Obama’s name, 78 percent of Democrats, 60 percent of Republicans, and 70 percent of independents support a path to citizenship as part of comprehensive immigration. But when you associate that proposal with the president, support drops to 75 percent of Democrats, 61 percent of independents, and just 39 percent of Republicans — a 21 point decline. Likewise, without Obama’s name, 65 percent of Democrats, 32 percent of Republicans, and 51 percent of independents support measures to address climate change. With his name attached, Democratic and independent support increases — to 71 percent and 55 percent, respectively — but Republican support dips even further, to 24 percent.

Obviously, partisanship has something to do with this — Republicans don’t want to associate themselves with Obama’s policies, and Democrats are more than happy to do so. But it’s important to note the extent to which this is an unavoidable fact of the bully pulpit. In his book, “On Deaf Ears,” political scientist George C. Edwards explains that presidential rhetoric rarely persuades and most often, energizes the other side. This was true for the “Great Communicator” Ronald Reagan, and it is true for Barack Obama.

It should be said that the Washington Post shows one exception to this rule. When Obama’s name is associated with gun control — and in particular, a new assault weapons ban — support goes up among all groups. For Democrats, it goes up from 60 percent to 76 percent. For independents, it goes up to 50 percent from 43 percent. And for Republicans, it goes up one point, from 30 percent to 31 percent.

That might be a quirk of the methodology, or it might be a sign that — since Sandy Hook — a new consensus has formed around gun control. And as a result, Obama’s rhetoric does more to help the cause than hurt it.

Jamelle Bouie is a staff writer at The American Prospect, where he writes a blog.