AUSTIN, TX & SANTA FE, NM (By Chris Tomlinson, AP) March 12, 2012 ― Rarely does the Texas governor, attorney general, state comptroller and House speaker heap praise on a freshman lawmaker, but that's what happens when a Hispanic state representative becomes a Republican at a time when the party considers its dominance in danger.

Gov. Rick Perry congratulated Harlingen Rep. J.M. Lozano for placing personal convictions over party loyalty. Attorney General Greg Abbott pledged the Republican Party's support for Lozano and all Hispanics who want to join the party that places God over government.

Perry didn't shy away from why.

"For the Republican majority to continue to grow and expand we need a new generation to step forward. We need those fresh faces from communities where our party has underperformed," Perry said on Thursday. "In particular, we need those Hispanic leaders to carry the banner of the party."

But if history and the current political mood are any indication, grassroots Republicans are a little less welcoming to newcomers than the state's top elected officials.

Lozano follows in the footsteps of Rep. Aaron Pena, another Hispanic from the Rio Grande Valley who switched parties last year. Pena served four terms as a Democrat before switching parties, and once inside the Republican caucus he stayed true to his relatively moderate politics.

But Pena's first year as a Republican also turned out to be a redistricting year. His Republican colleagues drew Pena into a district where he stood little chance of winning. He chose not to run again, but remains a loyal member of the party.

Republican lawmakers did a better job drawing a friendly district for San Antonio Republican Rep. John Garza, but a federal court redrew his district putting him in a Democrat-leaning race. He is expected to face a tough re-election bid.

Lozano's switch comes after he saw that new House District 43 voted for Republicans at the presidential level in the past, but they voted for Democrats in down-ballot races. This might help him in the general election, but first Lozano must survive a Republican primary challenge from Portland architect and Republican donor Bill Wilson and former Ingleside Mayor Willie Vaden.

Needless to say Democrats will target Lozano, especially after he accepted $147,000 from top party donors attorney Steve Mostyn and Texans for Insurance Reform. But some Hispanic Democrats predict he won't make it to the general election.

"Latino Republicans have the highest attrition rate of any caucus in the Legislature this cycle," said Rep. Trey Martinez Fischer, a Democrat who leads the Mexican American Legislative Caucus. "Out of six Latino Republicans, only one may be back next session. This loss rate is proof positive that Texas Latinos face significant obstacles to advancement in the Texas Republican Party."

Republican primary voters surprised political observers in 2010 when they ousted incumbent Railroad Commissioner Victor Carrillo to nominate little-known accountant David Porter to run in the general election. Carrillo said he lost because of his Spanish surname.

But the problem is not only about ethnicity. Former Democrats have a hard time convincing Republican primary voters that they are dyed-in-the-wool conservatives in a year when that matters most. Party activists distribute scorecards based on voting records that make it hard for many veteran Republicans to defend themselves against right-wing attacks, little alone someone who voted with fellow Democrats just last year.

Another Democrat who became a Republican in 2010 is Rep. Alan Ritter from Nederland, near Port Arthur. He received a failing grade from influential conservative group Texans for Fiscal Responsibility and is facing a Republican primary challenger who doesn't hesitate to paint the incumbent as a moderate.

Rep. Chuck Hopson of Jacksonville switched to the Republican Party in 2009 and won re-election in 2010. But Texans for Fiscal Responsibility gave Hopson a letter grade of D for his voting record and endorsed conservative challenger Travis Clardy, an East Texas attorney.

"Travis Clardy has demonstrated himself to be a strong conservative who is best suited to represent the values and principles of East Texas' voters," said the president of Texans for Fiscal Responsibility, Michael Quinn Sullivan. "In Travis Clardy, taxpayers will have a legislator who opposes new taxes, fights for a stronger Texas economy, and limits government spending."

With the primary election taking place the day after Memorial Day and a run-off on July 31, political analysts predict party activists will play a major role in the results. But how well conservative Republicans do in the general election will depend a lot on what happens in the presidential race.

Lozano's re-election bid as a Republican will be watched as a bellwether for Hispanics in the Republican Party in the primary election, and then as gauge of Republicans' chances in Hispanic-majority South Texas in the general election.

Chris Tomlinson is the supervisory correspondent in Austin and is responsible for the AP's state government and political reporting in Texas.