Turns out Milwaukee isn't the only place where

AirTran

( AAI) wants to grow.

Beginning this summer, AirTran will add flights between Las Vegas and seven other cities, six of them in the Midwest. While most of the destinations will have seasonal service with less-than-daily frequencies, AirTran has a history of growing occasional flights into regular ones -- and of expanding beyond the East Coast.

"This is part of diversifying our network," says Kevin Healy, vice president of planning. "If you look at the last several years in terms of east-west flying, we had none in 2003, but this summer a quarter of our capacity will be east-west longhaul."

The new destinations include Akron and Dayton, Ohio, Bloomington, Ind., and Flint, Mich. Milwaukee service begins July 10.

Milwaukee is the hub for

Midwest

( MEH), which AirTran is trying to acquire for $389 million, against the wishes of management of the target company. However, by simply building Milwaukee service, AirTran is hoping to signal that it can serve the city whether the hostile takeover effort succeeds or not.

Last month, Midwest shareholders voted to place three directors on the board who were nominated by AirTran. Following the vote, Midwest CEO Timothy Hoeksema said it suggests "that our shareholders want us to listen, and that is what we intend to do."

All of the new destinations clearly fit AirTran's growth model. "We start on a seasonal basis, and as markets develop, we go to year-round, and then we go to more flights," Healy says. "That's what we did in Orlando and other Florida markets." Now, Las Vegas is on the list.

Las Vegas is not exactly an undiscovered market. Fast-growing McCarran International served 46.2 million passengers in 2006, making it the world's 11th busiest airport and the nation's sixth busiest.

Top airlines are

Southwest

(LUV) - Get Report

, with 37% of the traffic, and

US Airways

(LCC)

with 17%, according to the Bureau of Transportation Statistics.

In fact, Las Vegas is the top airport for Southwest, with 231 daily departures to 53 destinations. US Airways has 133 daily flights to 60 destinations, including a bank of flights between midnight and 2 a.m.

Besides limited service by all of the major carriers, Las Vegas also has discount carrier

Allegiant

(ALGT) - Get Report

, which serves 39 cities with infrequent schedules that involve about 18 daily departures.

"You don't want to cross swords with Southwest or Allegiant, but AirTran will do fine," says aviation consultant Mike Boyd. "They have a lot of airplanes coming in, and Vegas is a good place to put the airplanes and try to make money."

Allegiant focuses on leisure travelers visiting Las Vegas from small cities, such as Biloxi, Miss., and Rapid City, S.D., and it does not view AirTran's new flights as competitive, says spokeswoman Tyri Squyres.

"It is normal for AirTran to reposition some flights from Florida," she says. Allegiant's business model includes the use of older MD-80 aircraft, onboard sales of tickets, beach towels and other goods.

AirTran's particular interest in Las Vegas, Healy says, is that the city has evolved from being primarily a market for gamblers to one that has considerable convention and business traffic.

"Las Vegas has changed a lot," he says. "Legacy carriers always viewed it as someplace where you couldn't make money, but frequent fliers liked it. Now the city and the casinos focus as much on meetings as they do on gambling."