Nearly 20 potential candidates — senators, governors, business executives and more — have paraded through the state in recent days to curry favor with voters and court party leaders. Republican voters are cheering that contrast, and expect that the candidate who emerges from the GOP race will be battle-tested for the general election. In between speeches at the sold-out event, hopefuls stopped in southern New Hampshire towns, and voters crammed into diners and attended house parties. [...] the outcome in Iowa's Republican caucuses tends to be heavily influenced by religious and social conservatives, leaving many candidates to view New Hampshire as their main focus. In the past two presidential elections, New Hampshire Republicans have handed victories to the party's eventual nominees, politicians already well-known to the state. Besides Rubio, only Sens.