Kansas, Wyoming hold caucuses Saturday
Paul and Santorum both campaigned in the state on Friday, and Gov. Sam Brownback appeared with each without making an endorsement.
In Topeka, Paul told an audience of about 500 that Kansas should be a "fertile field" for his libertarian-leaning views but declined to say how many delegates he hoped to gain.
Santorum, who hopes to drive Gingrich from the race in the coming week, lashed out at Obama and Romney simultaneously in remarks in the Kansas capital city.
"We already have one president who doesn't tell the truth to the American people. We don't need another," he said.
The former Pennsylvania senator told reporters he was confident "that we can win Kansas on Saturday and come into Alabama and Mississippi, and this race should come down to two people."
An aide to Gingrich said earlier in the week the former House speaker must win both Southern primaries on Tuesday to justify continuing in the campaign. But Gingrich strongly suggested otherwise on Friday as polls showed a tight three-way contest in Alabama.
"I think there's a fair chance we'll win," the former House speaker told The Associated Press about the contests in Alabama and Mississippi. "But I just want to set this to rest once and for all. We're going to Tampa."
Romney had no campaign appearances Saturday. The former Massachusetts governor won six of 10 Super Tuesday states earlier in the week, and hopes for a Southern breakthrough in Alabama on Tuesday after earlier losing South Carolina and Georgia to Gingrich.
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