Former Sens. Judd Gregg (R-N.H.) and Mel Martinez (R-Fla.) have endorsed Mitt Romney for president. 

The endorsements are especially helpful to the GOP front-runner because each comes from a respected politician in an early-voting state. Romney's campaign announced the two endorsements Monday morning.

Gregg, the top Republican on the Senate Budget Committee until his retirement last year, also backed Romney in 2008. Gregg nearly joined the Obama administration as Commerce secretary in 2009 before deciding his conservative economic positions would make it impossible for him to work for the Obama White House. He also is a columnist for The Hill. 

Martinez is a former chairman of the Republican Party and also served as secretary of the Housing and Urban Development Department under former President George W. Bush. He endorsed Arizona Sen. John McCainJohn Sidney McCainThe Memo: Trump’s media game puts press on back foot Meghan McCain shreds Giuliani for calling Biden a 'mentally deficient idiot' Mueller warns of Russian midterm attack, while Trump attacks Mueller MORE (R) in 2008.

The endorsements from two respected former senators could be helpful in the early-voting states they represent. New Hampshire will likely host the first primary, while Florida is set to be fifth in the pecking order and will be the first large state to vote in the GOP primary. 

Romney, who owns a home in the Granite State, has led in all New Hampshire polls in the last year and is expected to win the state. Florida, where Romney's second-place finish in 2008 behind McCain hurt his momentum, could be the key state in this year's nomination process.