John McCain to endorse Mitt Romney in New Hampshire

Sen. John McCain (R-Ariz.) endorsed Republican presidential candidate Mitt Romney Wednesday morning.

News of the endorsement broke Tuesday night ahead of the Iowa Caucuses, when a former aide to McCain told BuzzFeed that the 2008 Republican presidential candidate had plans to endorse Romney in the key early primary state of New Hampshire.

The endorsement comes just after Romney won the Iowa Caucuses, emerging victorious over former Sen. Rick Santorum (R-Penn.) by a razor-thin margin of just eight votes.

This is a developing story... More to come...