Story highlights Democrats in Nevada are gathering to caucus for their presidential nominee while Republicans in South Carolina are voting in the first-in-the-South primary

Results from both will tell us much about the future of the race and the strength of the contenders

(CNN) Hillary Clinton defeated Bernie Sanders in Nevada, suggesting her firewall could be secure. Meanwhile, Republicans in South Carolina are voting in the first-in-the-South primary. Results from both will tell us much about the future of the race and the strength of the contenders.

Here's what to watch and what we've learned so far on Saturday.

Clinton not Berned; Nevada as a thermometer

Sanders surpassed expectations in New Hampshire by delivering a wallop to Clinton after nearly tying her in Iowa. But his defeat in Nevada -- Clinton led 52% to 47% with three quarters of the vote counted -- suggests the senator from Vermont needs some organizational prowess to match the excitement he has created among younger and more liberal voters if he is to deliver a true, long-term challenge to the former secretary of state.

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The win was anything but assured heading into the Saturday contest. Clinton's campaign initially projected confidence in Nevada, pointing to her appeal to the state's Latino voting population, but after New Hampshire, her team softened the rhetoric about the western state. Clinton's wins means she can begin to firm up the conventional wisdom that she still is the inevitable nominee.

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