Des Moines, February 1 (RHC)-- The road to the White House begins in the U.S. state of Iowa tonight, as voters gather for political caucuses. Registered voters will select their pics for the Democratic and Republican nominations, with polls showing tight races on both sides.

Republican front-runner Donald Trump holds a small lead over Texas Senator Ted Cruz in Iowa. In the Democratic race, Vermont Senator Bernie Sanders has rallied to close what was once a 40-point deficit behind Hillary Clinton.

As the first in the U.S. to vote on presidential hopefuls, the Iowa caucus plays an major role in the election cycle. Voters have been treated to months of visits from candidates and more than $150 million in political advertising.