Getting involved in party primaries once was considered politically taboo for contentious lawmakers, but the practice now appears to be gaining popularity as an increasing number of Members this cycle have demonstrated a willingness to step out on a limb and endorse in intraparty fights.

In the past two weeks alone, at least five Members have announced they are backing their favored candidate in various open-seat House and Senate contests across the country.

On Monday, Rep. Corrine Brown (D-Fla.) announced she is endorsing fellow Democratic Rep. Peter Deutsch (Fla.) in the open-seat race to replace retiring Sen. Bob Graham (D-Fla.). Deutsch currently faces a three-way primary with former state Education Commissioner Betty Castor and Miami-Dade Mayor Alex Penelas.

In a conference call with reporters, Brown said she wanted to make the endorsement early in the process, and she added she thought Deutsch’s “frenetic style” would serve the party well.

The backing of the state Democratic Party’s highest-ranking woman will no doubt help Deutsch’s efforts to reach out to voters beyond his South Florida base, especially those in the black community. Brown, who is black, represents the northern 3rd district that stretches from Jacksonville to Orlando.

But while some Members seek to publicize their endorsements, others are more low key.

Freshman Rep. Tom Feeney (R-Fla.) recently endorsed former state Rep. Connie Mack (R) in his bid to capture the open 14th district seat, but he did not do any press or widely publicize the endorsement.

Feeney served with Mack, the son of former Sen. Connie Mack (R-Fla.), in the state House where he was Speaker before being elected to Congress in 2002. The younger Mack faces at least two primary opponents in the race to succeed retiring Rep. Porter Goss (R-Fla.).

By and large, the recent spate of Member endorsements have come in GOP primaries.

Rep. Henry Hyde (R-Ill.) last week announced his support of state Sen. Steve Rauschenberger, one of at least six Republicans who is vying to succeed retiring Rep. Peter Fitzgerald (R-Ill.). While several Democrats in the state’s Congressional delegation have waded into the Democratic Senate primary, Hyde is the first GOP Member to do so.

“It’s not politically astute,” Hyde conceded in an interview last week. “But he asked me, and he is a township chairman in my district.”

Hyde said if his endorsement could help Rauschenberger, he saw no reason to withhold it. He also stressed that his endorsement was “by no means to demean the other candidates.”

“But only one can win,” he added.

Among Democrats in the Land of Lincoln, Reps. Danny Davis, Jesse Jackson Jr. and Bobby Rush, the three black Members of the delegation, have all opted to take active roles in the Senate primary.

Davis and Jackson are supporting state Sen. Barack Obama’s (D) campaign, while Rush signed on earlier this year as chairman of millionaire investment banker Blair Hull’s (D) Senate bid.

Although at the time Rush claimed his decision to back Hull was not personal, his past history with Obama — who challenged Rush in a 2000 primary — was viewed as a factor in the endorsement.

Rep. Lane Evans (D) has also endorsed Obama in the race.

Meanwhile, state Comptroller Dan Hynes has touted his endorsement by Rep. Jerry Costello (D) in his effort to make the case that he is the only candidate in the race who can appeal to downstate voters. Costello and Evans are the only two Democrats in the state delegation who represent districts outside of the Chicago media market.

While the Illinois Senate race does not include any sitting House Members, there are lawmakers lending a hand to colleagues who are looking to move to the Senate next year in other states.

Rep. Jim DeMint’s (R-S.C.) Senate campaign will get a boost tonight at a Washington, D.C., fundraiser hosted by GOP Sens. Saxby Chambliss (Ga.) and Don Nickles (Okla.) and Ohio Reps. John Boehner, Mike Oxley and Rob Portman.

Recently, National Senatorial Campaign Committee Chairman George Allen (Va.) was among the hosts of a fundraiser for former state Attorney General Charlie Condon (R), one of DeMint’s top primary rivals. Sens. John Cornyn (Texas) and Jeff Sessions (Ala.), both of whom are one-time state attorneys general, also hosted the event for Condon.

Allen’s presence on the Condon invitation did not constitute a formal endorsement and the NRSC chairman has also done an event for DeMint.

It has become an increasingly common practice for Members to lend their names to fundraisers for primary candidates, without issuing a formal endorsement in the race.

There are other instances where lawmakers will issue a non-endorsement endorsement, by finding ways to back candidates without making a formal statement.

“I don’t do endorsements in primaries,” Chambliss said, when asked recently about his involvement in Georgia’s 8th district open seat race.

Chambliss attended a fundraiser for state House Minority Leader Lynn Westmoreland (R), the leading candidate in the race to replace Rep. Mac Collins (R-Ga.), earlier this year and in brief comments at the event he pledged to do what he could to assist Westmoreland.

“Lynn is a longtime dear friend,” Chambliss explained last week. “He was very active in my primary, as well as my general, and I’m doing everything I can to make sure Lynn’s got the resources to get his message out.”

Asked whether he considered that an endorsement, Chambliss responded: “You can interpret that however you want.”

Aside from personal friendship, Members base their endorsements on a number of factors, including ideology, geography and, in the case of Rep. Charlie Norwood (R-Ga.), occupation.

Norwood and Rep. John Linder (R-Ga.) went public last week with their endorsement of state Senate Majority Leader Tom Price (R) in his bid to succeed Rep. Johnny Isakson (R) in Georgia’s 6th district. Price faces three other state lawmakers in the July 2004 primary.

Norwood, a dentist, said he and Price, an orthopedist, “go way back,” but in the end he said he decided to go with the candidate he felt would support his health care initiatives.

But while there is evidence of some lawmaker involvement in the Peach State’s two open-seat Congressional races, Members of the state’s GOP delegation — more commonly known as the “G-8” — are staying out of next year’s Senate primary, which pits Isakson and Collins against each other.

Meanwhile, in California, several Members are taking opposite sides in two open-seat races, both of which are considered fairly safe bets to be retained by the party that currently controls them.

In the 3rd district race to succeed retiring Rep. Doug Ose (R), state Sen. Rico Oller (R) has been endorsed by GOP Reps. Richard Pombo and John Doolittle, who are both personal friends.

Oller’s primary foe, former state Attorney General and ex-Rep. Dan Lungren (R), is backed by Republican Reps. Ken Calvert, David Dreier, Elton Gallegly and Gary Miller.

Pombo and Doolittle endorsed Oller before they knew Lungren was going to enter the race.

In the open 20th district primary to succeed Rep. Cal Dooley (D), former state Sen. Jim Costa (D) has the backing of Sen. Dianne Feinstein as well as Reps. Joe Baca, Howard Berman, George Miller, Juanita Millender-McDonald, Adam Schiff, Mike Thompson, Diane Watson and Maxine Waters, as well as several former Members of the delegation.

Ex-Dooley Chief of Staff Lisa Quigley, who is running to replace her old boss, has been endorsed by Dooley and Reps. Ellen Tauscher and Jane Harman.

But as Member involvement in primaries appears to be on the rise, party committees on both sides of the aisle and Capitol have largely shied away from formal endorsements so far this cycle.

The one exception is in Pennsylvania, where Sen. Arlen Specter (R) is being backed by the National Republican Senatorial Committee, the White House and other Republican leaders as he faces a primary challenge from Rep. Pat Toomey (R).

“We typically don’t get involved in competitive primaries,” said Democratic Senatorial Campaign Committee spokesman Brad Woodhouse.

On the House side, neither the National Republican Congressional Committee nor the Democratic Congressional Campaign Committee has formally endorsed any primary candidates so far this cycle, but they have found other ways of signaling their support.

NRCC Chairman Tom Reynolds (N.Y.) was an early supporter of state Sen. Charlie Dent (R), the leading candidate to succeed Toomey in Pennsylvania’s 15th district.

While Reynolds has hosted more than one event for Dent, who faces a primary with two other candidates, the NRCC has maintained it is remaining neutral in the race.