Constraining electroweak breaking from exotic scalars using LHC diboson searches

In the Standard Model, the electroweak symmetry is broken by the vacuum expectation value of an isospin-doublet scalar field, i.e. the usual Higgs field.  But could part of the observed electroweak breaking be caused by scalar(s) with higher isospin?  The answer is yes, and the possibility can be tested now through searches at the LHC.  Such models generically predict doubly-charged and singly-charged exotic Higgs bosons that decay to W or Z boson pairs and play an essential role in the theoretical consistency of the models.  I'll discuss searches for these exotic Higgs bosons within the prototype Georgi-Machacek model and how they constrain electroweak breaking contributions from a broad class of higher-isospin models.