Topeka ? More registered Republicans have cast early votes in Kansas than voters affiliated with other parties in the state, and GOP officials are trumpeting the data as a sign that Gov. Sam Brownback and U.S. Sen. Pat Roberts are headed toward re-election after tough races.

But Democrats and independent Senate candidate Greg Orman’s campaign differed with that interpretation, saying that GOP is trying to encourage conservative voters to get them to the polls on Tuesday. Paul Davis, the Democrat challenging Brownback, said Friday that polling consistently suggests that 20 percent to 25 percent of registered Republicans support him.

“We’ve been tracking the numbers, and we feel very good about how we’re doing,” Davis said after voting in advance in his hometown of Lawrence. “All the signs that we see so far are very positive.”

Recent polling suggests that Roberts’ race with Orman and Brownback’s contest with Davis are close. Secretary of State Kris Kobach is predicting voter turnout of 50 percent, or 872,000 ballots cast.

Nearly 153,000 people had voted as of Thursday, according to the secretary of state’s office. Of those, 54.2 percent were registered Republicans, 30.6 percent were Democrats and 14.9 percent were unaffiliated. Among the state’s 1.74 million registered voters, 44.6 percent are Republicans, 24.5 percent are Democrats and 30.2 percent are unaffiliated. Libertarians command less than 1 percent of either group.

Clay Barker, the Kansas Republican Party’s executive director, issued a memo to reporters saying the party is encouraged and expects a strong GOP turnout.

“Each day that goes by, these early voting numbers increase for Republicans and shrink for Democrats,” Barker wrote.

And following a rally for Roberts in Topeka, voter Bill Ferrill, a 76-year-old retiree, said he’s feeling better about the senator’s chances of re-election than he did a few weeks ago, though, “I’ve always felt that he would pull it out.”

Roberts told reporters: “I think we’ve turned the corner.”

But critics of Brownback and Roberts said Republicans are getting regular voters to cast their ballots earlier than normal, rather than turning out people who often skip midterm elections.

Orman spokesman Mike Phillips said the GOP’s early voting performance is “anemic,” and that voters are frustrated with Washington and see Roberts as part of the problem.

“They want somebody who will go to work for them and actually work to solve problems,” he said.

A recent poll of 767 likely voters by NBC News and Marist College in Poughkeepsie, New York, said both Davis and Orman led among those who had cast early ballots.

Jason Perkey, the state Democratic Party’s executive director, said Barker is out of touch with the electorate and trying to boost enthusiasm among GOP conservatives.

“They realize the only way for them to win is to gin up their base,” Perkey said.