US presidential elections 2016: Most amusing photos of candidates on the campaign trail

The race for the White House starts in earnest this week, as candidates try to win voters over during a four-week sprint to the Iowa caucuses.

For the Democrats the US presidential election is basically a two-horse race. Senator Bernie Sanders, a Vermont independent, hopes an upset in Iowa and a victory in the New Hampshire primary a week later will dent the apparent inevitability of front-runner Hillary Clinton. Wins in the first two states for the former first lady, New York senator and secretary of state would all but cement her place on her party's ticket.

There is no such clarity in the Republican race. Despite shedding five candidates before New Year's Day, this contest is an unpredictable mix of a dozen hopefuls with vastly different visions for the party and the country. While Texas Senator Ted Cruz has edged ahead in preference polls of Iowa voters in recent weeks, nationally he still trails the unquestioned political star of 2015, Donald Trump. The big question is: are the crowds at his rallies likely voters, or merely fans entertained by the outrageous sideshow? Could Jeb Bush, Marco Rubio, John Kasich or Chris Christie emerge as the clear alternative?

One thing is for sure, with nearly a year to go until the presidential elections, the candidates on both sides will be pulling out all the stops, making a lot of heartfelt speeches, kissing a lot of babies, and appearing in a lot more entertaining photos – like these.