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By Jon Herskovitz and Marice Richter
AUSTIN, Texas, March 3 (Reuters) - The longest shadow in Tuesday's primary election in Texas is being cast by a politician not even in the running, freshman U.S. Senator Ted Cruz, a Republican.
Cruz, just two years into his first major elected office, has arguably become the most loved politician among Republicans in Texas, an incubator for national conservative policies where the party dominates the statehouse and has not lost a statewide race since 1994.
A host of Republican hopefuls are trying to ride his coattails, turning campaigns into raucous affairs about how much they despise Obamacare, embrace the constitutional right to bear arms and see a need to raise alarms about illegal immigration.
Cruz has turned an already right-leaning Texas Republican Party even further to the right, analysts said.
"Cruz scared the daylights out of center and center-right conservatives to the extent that they do not feel comfortable enough to run on their true positions and feel compelled to cater to the most conservative elements of the Texas Republican primary electorate," said Mark Jones, a political science professor at Rice University in Houston.
Cruz, 43, a darling of Tea Party Republicans with their often unbending policies to shrink government, has mostly steered clear of direct campaigning in Texas but has supported a select few candidates challenging established Republicans.
Last year, Cruz led the push to deny funding to President Barack Obama's healthcare plan, resulting in a 16-day government shutdown. The strategy left congressional Republicans further divided, with moderates in the Senate unhappy about the public backlash against the GOP.
In Texas, support has grown for Cruz since the standoff, with 43 percent of respondents in a University of Texas-Texas Tribune poll in February having a favorable opinion of him, higher than the 33 percent favorable rating for fellow Senator John Cornyn, a Republican.
Cruz is also the top choice of Texas Republicans to be the party's nominee for the 2016 presidential race.
"Everyone wants to be the next Ted Cruz and pull off the startling upset," said Republican lobbyist and strategist Bill Miller of Austin.
Cruz's influence has grown since the state's most prominent elected official, Governor Rick Perry, announced in July that he would not seek re-election in 2014, fueling speculation he may try again to win the Republican race for president.
Cruz has not weighed in on the two biggest races in the Republican primary: the gubernatorial contest, in which Attorney General Greg Abbott is almost certain to win a landslide victory to be the party's candidate, and the U.S. Senate race, where Cornyn is set for an easy victory.
Analysts say tensions between the two senators reflect the divide within the Republican Party, where a staunch conservative like Cornyn is viewed with suspicion by the Tea Party for being an establishment politician who does not reject out of hand the idea of working with some Democrats to pass legislation.
In the Dallas area, U.S. Representative Pete Sessions is the most prominent Republican in the Tea Party firing line. Challenger Katrina Pierson's website features a picture of Cruz and a quote in which he calls her "an utterly fearless principled conservative."
In neighboring Fort Worth, Cruz has endorsed local Tea Party leader Konni Burton as the Republican nominee for a state Senate seat.
State Senator Ken Paxton, running in a crowded field for attorney general, has featured a comment on his website in which Cruz calls him a "conservative warrior."
Cruz may be playing his cards wisely. If he endorses Cornyn, hardcore Tea Partiers are likely to call him a sellout. If he openly campaigns for Tea Partiers, he could be more easily dismissed as a political outlier, analysts said.
Many Democrats are actually hoping for a greater Cruz influence in the race.
A hard-line Republican stance on immigration could eventually benefit Democrats. By 2020, the state's Hispanic population is projected to eclipse its white population.
"The state will not turn the blue of the Democrats in this election cycle," said Sherri Greenberg, director of the Center for Politics and Governance at the Lyndon B. Johnson School of Public Affairs at the University of Texas.
"But it is possible that if the Republican Party turns so far to the right with particular stances on immigration that it may hasten the day when that change comes," she said. (Editing by Douglas Royalty)