By CHRIS TOMLINSON, Associated Press

AUSTIN, Texas (AP) — The deaths this year of three major Texas Republican donors, including a billionaire who died over the weekend, could signal a generational change for party kingmakers in the nation's largest GOP stronghold.

Harold Simmons, whose business interests ranged from energy to nuclear waste dumps, helped transform Texas from a Democrat-controlled state in the 1970s to a Republican stronghold by the turn of the century. Simmons' death Saturday came after Republicans lost home builder Bob Perry in April and businessman Leo Linbeck Jr. in June. For decades, all three helped bankroll political campaigns both in Texas and nationwide.

All three men were considered conservative renegades when they got involved in politics. However, as the state grew more conservative, they became part of the GOP mainstream.

The loss comes as Texas Republicans already were facing a turning point. Gov. Rick Perry, one of the donors' biggest recipients, isn't seeking re-election next year, and a new breed of GOP candidates such as tea party-backed U.S. Sen. Ted Cruz has emerged in the state.

"It leaves a huge question mark for Republican candidates and political organizations that have relied on major contributions from those two or three individuals for the last decade," said Matt Mackowiak, a prominent Republican political consultant. "Their generosity made a huge difference in a lot of races over a long period of time, but it was their potential to always contribute more that probably prevented a lot of races from ever taking place at all by scaring off potential competitors.

The three men contributed to Republican candidates and organizations across the country, but their influence was greatest in Texas, which has no limit on personal campaign contributions.

Simmons, who had an estimated net worth of $10 billion, gave at least $12.6 million to candidates in Texas races since 2000, according to the Texas Ethics Commission. The Center for Public Integrity named him the second-largest donor to national political action committees for 2011-2012, giving away $31 million to conservative groups.

Houston tycoon Bob Perry, no relation to the Texas governor, made his fortune building tract homes across the state and made at least $75 million in political contributions in his lifetime, not counting confidential gifts to super PACs, which can campaign independently for candidates. He gave $4.4 million to the Swift Boat Veterans for Truth campaign, which sought to discredit Democrat John Kerry's war record when he challenged President George W. Bush in 2004. Simmons also gave the group $3 million.

Linbeck, whose family also made its fortune in construction, helped create two of the state's most influential conservative organizations, Texans for Lawsuit Reform and Americans for Fair Taxation. TLR spent millions on candidates who supported limits on lawsuits against businesses and AFT campaigns to replace the national income tax with a national sales tax.

The full extent of their donations may never be known, since many were made privately.

James Henson, director of the Texas Politics Project at the University of Texas at Austin, said there is a generational change taking place in the Republican Party that coincides with the growing fight between grass-roots tea party conservatives like Cruz, and the more pragmatic business wing of the party, represented by Texas House Speaker Joe Straus.

"We associate these guys with an era of Republican politics in this state that is in transition and possibly becoming something different," he said. "These were the guys who were the bedrock donors for the business wing of the Republican Party, and as politics has gotten more polarized, the party has a more ideological bent to it. These were guys in big business who were motivated by classical business interests."

An example of this pragmatism came in 2011, when Texas legislators debated a law that would have required local police to question the immigration status of the people they encounter. Bob Perry, whose industry relies on immigrants, opposed the measure, and Republican leaders made sure it expired without a vote.

So-called establishment candidates will suffer the most from losing these critical donors, said Rice University political scientist Mark Jones, an expert on Texas campaign finance. He said Perry and Simmons dwarfed all other Republican donors in Texas.

"The absence of someone like Perry or Simmons hamstrings (establishment candidates) in many respects, and their ability to use their financial advantage against tea party and movement conservatives," he said. "There is no one left now that has the gravitas to single-handedly decide whether a candidate runs or not, or is viable or not."

But Corbin Casteel, another Republican campaign consultant, said a new generation will step in to make up for the lost donations.

"While there may be a giving gap now, or in the short run, there is more out there," he said. "In West Texas (oil fields) there are a lot of new, wealthy conservatives who are just beginning to get involved in the political movement, we're looking at a whole new generation of major Republican donors coming onto the scene.

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