For Kansas Republicans, there’s no place like Johnson County.

That’s why Republican Reps. Jerry Moran and Todd Tiahrt have zeroed in on the GOP-rich suburban area in their primary for the Jayhawk State’s open Senate seat.

The two veteran House Republicans are squaring off next August in the race to succeed Sen. Sam Brownback (R), who is running for governor. The winner of the primary is all but certain to be the state’s next Senator.

Most local political observers assume Moran and Tiahrt will overwhelmingly win their respective Congressional districts in the primary next year — a

scenario that will likely net more votes for Moran, whose rural western Kansas district has about 30,000 more registered Republican voters than Tiahrt’s district.

Perhaps more important for Moran and Tiahrt, however, is Johnson County, which boasts the largest GOP population in the state: There were 170,200 registered GOP voters in the county in 2008. What’s more, the number of Republican voters and the total population in the county have increased over the past few election cycles.

Ronnie Metsker, the chairman of the Johnson County Republican Party, said both candidates have come calling often this year.

“They seem to pop in and out almost like they live there,— Metsker said. “They are both very present in this county, and they both seem to be working very hard.—

But, he added, more “moderate— Republicans are leaning toward Moran, and more “conservative— voters appear to be supporting Tiahrt in Johnson County.

Johnson County includes Overland Park and several first-generation suburbs in the Kansas City area. The county lies in the 3rd district, which is represented by Rep. Dennis Moore (D), even though the district has regularly voted for Republicans on the local and national levels in recent cycles.

A top aide to Tiahrt’s campaign said the county is filled with an ideological mix when it comes to Republican voters.

“Colin Powell and Dick Cheney would both be allowed to live in Johnson County. Good Americans live in Johnson County,— Tiahrt campaign spokesman Chuck Knapp said.

As evidence of the area’s importance, Moran’s campaign announced last week that several local Johnson County mayors were supporting his campaign. And earlier this summer, Tiahrt aides touted a straw poll in Olathe — the county’s conservative bastion — that showed him in the lead.

“The battleground is definitely northeast Kansas, and Johnson County is the big prize,— Knapp said.

Moran campaign manager Aaron Trost acknowledged the Congressman’s inherent advantage because his district is more Republican, but he also said that pulling big vote totals out of Johnson County will be important.

“I think the first district is going to be 30 percent of the overall vote,— Trost said. “I think the obvious battleground is in the two districts that neither candidate represents — the 2nd and the 3rd.—

Unlike the 3rd district, the 2nd district is an eclectic mix of rural areas, small cities and the state capital, Topeka. The main media market is Topeka, while the remaining half of the voters in the district are split between the Pittsburg and Kansas City markets.

Running television is also expensive in the Kansas City area, which is the largest media market in the state. That market is also the most inconvenient because it straddles two states: Kansas and Missouri.

“Johnson County is part of a bi-state area, so money is critical. You don’t buy the Johnson County market. You buy the metro-city market, half of which can’t vote for you,— said Lenexa Mayor Michael Boehm, who was one of several Johnson County mayors who announced his support of Moran last week.

At this point, Moran has the edge in the money contest. The Congressman reported $3.1 million in cash on hand at the end of June — more than twice as much as Tiahrt’s $1.4 million in the bank.

Christian Morgan, former executive director of the state GOP, said the $1 million difference between the two House Republicans will go a long way in Kansas.

“It’s going to be really, really hard for Congressman Tiahrt to overcome Jerry Moran’s money advantage,— Morgan said. “Having a million extra dollars, being able to do whatever you want when it comes to radio, mail, is a very important advantage.—

Moran’s money advantage exists in part because he has been able to stockpile cash because his district is a safe Republican seat. While Tiahrt has not had a remotely competitive race since redistricting in 2001, he has had to spend more money over the years because he represents a slightly more competitive Congressional district.

What’s more, several House Republican operatives — all of whom declined to talk on the record — pointed out that Tiahrt has been more generous to his GOP colleagues over the years than Moran.

According to finance reports on CQ MoneyLine, Tiahrt has given on average $100,000 more to his Republican colleagues each cycle since 2004. In the 2008 cycle, Tiahrt gave $166,600 to other GOP candidates, while Moran transferred $92,000 to his fellow Republicans.