Kansas Sen. Sam Brownback’s run for governor has created a scramble in his home state for congressional seats and sets up fellow Republicans for a return to their traditional dominance there in 2010.

Democratic leaders are still searching for a strong challenger for Brownback. And the only Kansas Democrat in Congress, Rep. Dennis Moore, isn’t seeking re-election, increasing the chances of a GOP sweep of the state’s delegation.

A few years ago, some Democrats suggested the state’s normal Republican red was morphing into purple, thanks to Kathleen Sebelius’ victories in two governor’s races and ability to draw votes from GOP moderates. Now, Sebelius is in Washington as U.S. health and human services secretary and her successor, Gov. Mark Parkinson, isn’t seeking a full term this year.

Republicans, anticipating a regime change, are brimming with ambition. Their primaries set for August for Brownback’s open Senate seat and U.S. House seats have drawn a total of 20 candidates so far.

Nationally, Republicans look to have a good 2010. And in Kansas, the expectations are even greater.

“If there is going to be a Republican wave anywhere in the nation in 2010, it will occur in Kansas,” said Whit Ayres, a GOP pollster in Alexandria, Va.

Brownback said he didn’t ponder the upheaval from his decision to leave the Senate because it was set long ago by self-imposed term limits, and “I had no idea what would follow.”

Kansas hasn’t had both an open Senate and governor’s race since 1950. In the past 100 years, it’s had three open contests for U.S. House seats only twice — in 1962 and also 1996 when Brownback won his Senate seat.

Democrats insist they’ll run competitive races and have a strong candidate for governor. But they also acknowledge the stiff challenge they face against Brownback in a state where the GOP has a better than 3-to-2 voter registration advantage and two Democratic governors have never been elected back-to-back.

“Going into it, you know he’s going to be a formidable candidate,” said state Senate Minority Leader Anthony Hensley, a Topeka Democrat. “We can’t kid ourselves.”

A similar challenge awaits Democrats in the Senate race. The only Democrat actively campaigning is Charles Schollenberger, a former newspaper reporter and editor from Prairie Village. Among Republicans, U.S. Reps. Jerry Moran and Todd Tiahrt are running.

Sebelius was the party’s best potential candidate but never expressed much interest in the race publicly.

Without a popular office holder as the Democratic nominee, party loyalty is traditionally the key factor in an open race, said Bob Beatty, a political scientist at Washburn University of Topeka.

“That default is ‘I’ll vote for my party, because that’s who I am,'” Beatty said.

Sebelius’ political success in a GOP-leaning state gave her a national profile, made her a potential vice presidential candidate in 2008 and won her a spot in President Barack Obama’s Cabinet. But she was term-limited as governor.

Brownback formally organized his governor’s campaign a year ago — three months before Sebelius’ confirmation as health and human services secretary. Brownback faces only token opposition in the GOP primary.

If he ran for re-election to the Senate, Brownback probably would not face a strong challenge, and Moran and Tiahrt would stay in the House. But when Brownback first won his Senate seat, he promised not to serve there past 2010.

Some Democrats believe Brownback really is positioning himself for a future run for president after a brief, ill-fated campaign in 2007. Four of the last six presidents were governors first.

Brownback said he sees opportunities as governor — and a need — to position Kansas for sustained economic growth with low-tax and business-friendly policies. But he said his decision to run rests on keeping his promise about term limits.

“I said it, and I meant it,” he said, adding that some supporters urged him to forget the promise. “I ran on term limits. I believe in term limits.”

Meanwhile, Moran and Tiahrt’s runs for the Senate have opened up their seats in the 1st Congressional District of western and central Kansas and the 4th district in south-central Kansas.

The race in the heavily Republican 1st has attracted six GOP candidates and a Democrat who’s not given much chance to win, even in his own party. Five Republicans and two Democrats are candidates so far in the 4th, and Democrats have high hopes for their leading contender, state Rep. Raj Goyle of Wichita.

Republicans hope to pick up Moore’s seat in the GOP-leaning 3rd, centered on the Kansas City metropolitan area, where six Republicans are campaigning. The only Democrat so far is Elizabeth Gallup, a Lake Quivira doctor, but Kansas City Mayor Joe Reardon and former Mayor Carol Marinovich also have expressed an interest.

The state’s only U.S. House incumbent seeking re-election is Republican Lynn Jenkins in the 2nd District of eastern Kansas.