The prime-time speaking slots given to former New York Mayor Rudy Giuliani (R) on Monday and Empire State Gov. George Pataki (R) on Thursday will do more than just help burnish President Bush’s terrorist-busting credentials by conjuring up memories of the local response to the Sept. 11, 2001, attacks.

The speaking gigs will also boost each man’s gargantuan political ambitions.

With this week’s convention comes the latest chapter in the long, convoluted history between the two men who helped soothe a grieving city and nation in the aftermath of the terrorist strikes — and who personify the New York GOP’s modest Renaissance this past decade.

It’s no secret that both Giuliani and Pataki are eyeing White House bids in 2008 — a fact that tantalizes political observers throughout the Empire State. But however ascendant their stars appear to be, it is hard to imagine a scenario in which two moderates from the same Northeastern state emerge victorious in the Republican primary process.

“I certainly don’t think the national Republican Party is big enough for two presidential wannabes from New York,” said Howard Wolfson, a New York-based Democratic strategist.

“They’ve been on a collision course for 10 years now,” added Wayne Barrett, senior editor at the Village Voice and author of a biography of Giuliani published in 2000. “I think they’re on a major collision course for 2008.”

The irony is that as Pataki and Giuliani jockey for a prime position at the 2008 starting gate, the New York Republican Party they helped resuscitate appears to be on a downward spiral, with a tattered grassroots operation and few bankable rising stars.

And as Pataki and Giuliani seek to project themselves ever further onto the national stage by criss-crossing the country on behalf of Bush and other Republican candidates, neither seems willing to come to the aid of their beleaguered state party.

At least as intriguing is the question of how Giuliani and Pataki get along with one another these days, and how — if at all — they will be able to reconcile their competing interests.

In 1994 — when Pataki, then an obscure freshman state Senator, was defying the odds by taking on entrenched three-term Gov. Mario Cuomo (D) — Giuliani, then in his first year in City Hall, famously endorsed the Democrat.

Giuliani, according to Barrett and other political observers, had designs on the state party and viewed Pataki as a rival even then. What’s more, Giuliani had a less than chummy relationship with one of Pataki’s chief patrons, then-Sen. Al D’Amato (R-N.Y.) — though several New York Republicans say that D’Amato, who has profited handsomely from his association with the governor since leaving the Senate, was himself not convinced that Pataki was ready for prime time until late in the 1994 campaign.

After Pataki’s upset victory, the usually-cocksure Giuliani was humbled, as Pataki, and D’Amato, stocked state government with patronage appointments. But by most accounts, the governor and mayor maintained a professional relationship, even if there was plenty of sniping between their staffs.

Still, Giuliani’s endorsement of Cuomo remains an issue that Republican stalwarts throughout the country cannot forget.

“That is an indelible part of the record when it comes to political combat,” said Gordon Hensley, a former top aide to Pataki who has also worked for D’Amato, presidential campaigns and the National Republican Senatorial Committee.

Fast-forward to 9/11. Since the World Trade Center trauma, say Republican officials and operatives, the working relationship is stronger than it has ever been. But some Pataki allies resent the fact that “America’s mayor” parlayed his post-Sept. 11 performance into riches and superstardom, while Pataki is still stuck in Albany balancing budgets and dealing with a recalcitrant Legislature.

“If you’re Pataki’s staff, you sit around and say, ‘OK, where should we go this weekend: Batavia, Utica or Plattsburgh?’” said one New York Republican. “If you’re Giuliani’s staff, you say, ‘Rome or London?’”

Pataki intimates, insiders say, think a lot about Giuliani these days. Giuliani’s advisers, by contrast, are having too much fun and making too much money to worry about Pataki.

Although Giuliani may have more star power, Pataki has been no slouch when it comes to helping Bush and the national GOP.

While Giuliani has jetted around the country for the past two election cycles aiding Republican candidates up and down the ballot, he has mainly limited his activities to personal appearances. Pataki, by contrast, has personally raised millions of dollars for the president and other Republican committees. It’s a distinction that has not gone unnoticed in GOP circles.

“Assuming Bush wins, Pataki has some claims on him,” said Maurice Carroll, director of the Quinnipiac University Polling Institute, which polls in New York.

Pataki’s fundraising network can easily be tapped for a presidential campaign, Hensley said. “I’d say his fundraising and resource base are as formidable as anyone in the country.”

And Pataki may have other advantages over Giuliani when it comes to wooing the national GOP establishment.

Although both are moderates by national Republican standards, Pataki has cut taxes and is considered more conservative than Giuliani on social issues. He reinstated the death penalty in the Empire State and opposes some late-term abortions. Giuliani is a full-blown supporter of abortion rights, opposes a Constitutional ban on gay marriage and lobbied Congress for gun control measures when he was mayor.

Moreover, Pataki appears to have a stable home life; Giuliani is on his third wife, and his high-profile divorce from TV personality Donna Hanover a few years back was anything but amicable.

Although his very association with the Sept. 11 tragedy may be one of the reasons why Pataki was invited to introduce Bush at the convention Thursday night, he is expected to emphasize his own fiscal conservatism — as well as the president’s — during his 15 minutes of fame.

“Rudy has this 9/11 knighthood,” Barrett said. “And if terrorism is the giant issue [in 2008], then Rudy doesn’t have to worry about George Pataki. If it’s a more normal year, I think Pataki would be more acceptable to the Republican base and would be a stronger candidate.”

Before either can focus on 2008, both Giuliani and Pataki have some decisions to make about the next few years — decisions that might affect their presidential ambitions.

Will either be offered and accept a Cabinet appointment if there is a second Bush term? Would Pataki, whose poll numbers at home are slipping, consider seeking a fourth term in 2006, when one or two strong Democrats are likely to run for governor? The last New York governor to win a fourth term was Nelson Rockefeller (R) in 1970.

If Pataki doesn’t run again, would Giuliani seek his job? And would Giuliani or Pataki challenge Sen. Hillary Rodham Clinton (D-N.Y.) — a race that would instantly become the most watched contest of the 2006 cycle? Several observers, however, doubt that either man welcomes a fight with Clinton — or even wants to serve in the Senate — even though whoever manages to defeat the former first lady would surely be a hero to national Republicans.

“I think both of them are executive types,” said Michael Long, chairman of the New York Conservative Party, who is close to Pataki. “You usually don’t go from governor to U.S. Senate, especially if you’re governor of New York. Or if you’re mayor of New York. That’s a huge job.”

Other observers note that, other than his aborted campaign for Senate in 2000, Giuliani has not actually run for public office since his 1997 re-election. If he runs for governor in 2006 and wins, Giuliani probably wouldn’t be able to run for president two years later.

“I don’t think it’s in Giuliani’s interests to go against anybody, unless it’s for president,” Carroll said. “But Giuliani’s a scrapper, so he might decide, ‘What the hell, I’ll beat someone up on the way to president.’”

Carroll said that while it is more difficult right now to project Pataki’s next move, “he’s a winner.”

If, as assumed, both Giuliani and Pataki want to run for president in 2008, would they run against each other? Or would they try to work something out? If it’s the latter, there don’t appear to be any obvious intermediaries.

“I think if they’re put in a small room, the likelihood of them snarling at each other is greater than them coming to some kind of agreement,” Wolfson said.

But Hensley predicted that Giuliani and Pataki would meet to discuss the presidency — and wish each other luck.

“It’s a Darwinian world,” he said. “I wouldn’t go into a room and hash it out. Rather, it becomes a handshake and see what happens.”

The real danger, he said, is for New York Republicans, who would likely divide into competing camps — not an ideal situation for a party that is already a minority in its state.

One thing is certain: As Giuliani and Pataki prepare for their speaking assignments this week, the stakes may be higher for Pataki than for Giuliani, who at this stage is unquestionably better-known. Pataki is working with speechwriting guru Peggy Noonan on his address.

“This is probably the most important speech of his career,” Hensley said.