Rubio: Yes, just days after 2012 election, but has been largely holding off on a new wave of trips to early voting states. That's changing.
Ryan: Yes, was keynote speaker for Iowa GOP's big fundraising dinner in Cedar Rapids in April. Main speaker at governor's annual birthday fundraiser in November 2013, in first visit since 2012 campaign.
Santorum: Yes, recent visit with strategists and media. August 2013 speech to conservative Christians in state where he won the 2012 caucuses. Screened his new Christmas movie in Iowa in November.
Walker: Yes, fundraiser last year.
GO TO NEW HAMPSHIRE: Nation's first primary comes after Iowa and is just as important.
Biden: Yes, raised money for three Democrats in March visit for job-training event. Quipped: "I'm here about jobs — not mine."
Clinton: No. But Ready for Hillary has sent people there this year.
O'Malley: Yes, spoke at Democratic Party dinner in November. Also spoke at 2012 convention of New Hampshire Democrats.
Christie: Yes, three times in 2012.
Cruz: Yes, three times since August.
Jindal: Yes, keynote speech to local Republican organization in March, headlined state GOP fundraiser in 2013, visited twice in 2012.
Paul: Yes, addressed Freedom Summit in April. Won straw poll at March meeting of Northeast Republican Leadership Conference in Nashua. Several visits last year.
Rubio: Yes, splashy debut in May, first visit of the 2016 season, headlining fundraisers, meeting local officials, giving interviews. Multiple visits before 2012 election.
Ryan: Yes, headlined Manchester fundraiser in February for former House colleague. Canceled October 2013 visit because of government shutdown.
Santorum: Yes, March speech to Northeast Republican Leadership Conference marked his return to a state where he performed weakly in 2012 campaign.
Walker: Yes, headlined a GOP state convention in October 2013, keynote at state party convention in September 2012.
DON'T FORGET SOUTH CAROLINA: First Southern primary and big in its own right.